Its square shape is a bit of a departure from the more typical round, which has turned this doughnut into a social media sensation. The Dupont Circle go-to (which also serves a twist on Southern chicken and waffles) fills its most-popular doughnut with vanilla custard pastry cream, tops it with vanilla glaze and torches it for that signature caramel-flavored bruleed finish.

Like a mash-up of brown butter brickle ice cream and hazelnut biscotti, the Brown Butter Hazelnut Crunch doughnut at Union Square Donuts is crafted using a butter-based brioche dough (which gives it a light and airy, almost pastrylike texture, according to co-owner Josh Danoff). It’s topped with a butter glaze and sprinkled with toasted, crushed hazelnuts, and it's a perfect example of the globally inspired doughnuts at the Somerville store.

After creating churro-inspired treats for Cinco de Mayo, Pink Box Doughnuts (where pastry chefs bake for a staggering 18 hours each day) decided to offer them the entire year, not only in celebration of Mexico’s independence. Their long, glazed bar has a freshly fried and cinnamon-garnished churro sunk into the middle, and it is topped with a generous amount of creamy dulce de leche.

Housed in an old print shop on the back side of Indianapolis’ Fountain Square district, General American Donut Company is decorated with mid-century modern furniture, industrial finishes, and funky and pop culture accents. Like the candy of the same name, the raised Salt Caramel doughnut is a yeast doughnut frosted with housemade caramel and sprinkled with sea salt. (It’s perfect with the Stumptown Coffee they brew too.)

Who can resist a nice crispy piece of bacon? Not many people who walk into this family-owned German-American bakery in Louisville, that’s for sure. The Maple Bacon doughnut at Nord’s Bakery starts with a hand-crafted yeast long john; it's topped with homemade maple glaze and a slice of bacon. “It’s the perfect balance of sweet and salty,” says owner Mike Nord. "Breakfast and dessert rolled into one yummy pastry!"

The ever-changing eclectic daily flavors at this New American restaurant in Denver include mint-bourbon, five spice and pomegranate; no matter the flavor, they are usually history by lunchtime. Taking a cue from a popular summer salad flavor, this sweet, sour and savory doughnut is covered with a strawberry glaze, topped with a doughnut hole and drizzled with balsamic vinegar.

When Sugar Shack founder Ian Kelley was researching and testing flavors to open his shop, he used whatever happened to be in his fridge at the time, including strawberries. Today the strawberry-glazed variety is made with fresh strawberries over a yeast-raised doughnut. Co-owner Tanya Bartek says it just tastes like summer. “Every bite tastes eerily like eating the perfect berry straight from the field.”

It may take 36 hours using old-world techniques, but Doughnut Vault’s classic vanilla doughnut is well worth the effort. Batches are lovingly rolled, cut, proofed and fried fresh every night, then topped with a classic vanilla bean glaze that complements the buttery pastry underneath. It looks massive and intimidating, but is light and fluffy, and gone all too quickly.

When Seattle’s Top Pot Hand-Forged Doughnuts & Coffee first opened its doors in 2002, the owners put Ovaltine lattes on the menu. The popularity made them realize it would be a natural thing to showcase in doughnut form. A yeast-raised bismarck doughnut is piped with a chocolatey, malty Ovaltine-custard filling and topped with a light sprinkling of powdered sugar, for a nod to a beverage that was many staff members’ childhood favorite.

Its strikingly gorgeous hue is the first thing that attracts customers to the Hibiscus Doughnut at Dough, a cult-favorite Brooklyn-based shop. Chef and founder Fanny Gerson hails from Mexico, and one day while developing flavors, she craved hibiscus water. She bought some flowers at a Mexican deli nearby, and as she was drinking the water she pictured a doughnut glaze. The result is heady, exotic, slightly tart and ready for photos.

It takes three days to make the 100 Layer Donut, in which croissant dough is used to create a light and flaky appearance and texture. Flavors include chocolate with sea salt, a vanilla cream and seasonal fruit flavors. The King Kong is flavored with maple and topped with locally sourced bacon, making for a monster of a pastry good anytime.

Gooey butter cake, a flat, firm, dense cake made with wheat cake flour, butter, sugar and eggs, is a St. Louis specialty. Strange Donuts’ Gooey Butter option captures the coffee cake’s richness, complete with its delicate dusting of powdered sugar. Natives to the city respect the shop’s take on the culinary tradition, while tourists are happy to be able to find a portable version to tote around town.

“Creatively glazed and finished with housemade toppings” touts the menu of New Orleans’ District Donuts when it comes to the Fancy doughnut, an ever-changing creation that might include garnishes like crumbled Oreos, rainbow sprinkles and tasty glazes. Order one with a drip coffee, chocolate milk or nitrogen-cold drip coffee from their line of taps, and while away time in the Big Easy.

Irreverently named? Perhaps. Decadent? Absolutely. Inspired by chicken and waffles, the sweet-meets-savory doughnut comes from Gourdough’s, a shop that got its start in a vintage Airstream trailer. A piping-hot doughnut is piled with crispy Southern-spiced fried chicken strips and smothered in warm honey butter. Skip the coffee and wash this one down with a local beer or a cocktail.

Funky Albuquerque shop Rebel Donut likes to dabble both in pop culture and in traditional New Mexican ingredients. One example is their ode to a warm stack of flapjacks on a lazy Saturday morning. A blueberry pancake-inspired doughnut is topped with a drizzle of maple syrup. It's sticky, sweet and a quicker sugar rush than heating up the griddle.

Unabashedly supersized and decadent, this doughnut (which comes in three varieties: s’mores, blueberry and strawberry) arrives stuffed with a full-sized toaster pastry. Customers are known to line up at the door hours before the shop opens to snag one of the 120 sold daily, and celebrities including Ellen DeGeneres, Ryan Seacrest and Duff Goldman call themselves fans.

Opened in 2014, Glaze Donuts, a small chain of shops around the state, uses only the highest quality natural ingredients, with no preservatives, high-fructose corn syrup or artificial colorings. (And they’ve also partnered with Uber for a doughnuts-on-demand National Doughnut Day charity event.) Their yeast-based Maple Bacon doughnut is topped with a maple glaze and bacon bits for a result that’s savory, sweet, salty and utterly addictive.

You know that mashed purple starch that's part of every Hawaiian luau? It becomes dessert inside these fluffy doughnuts, at Liliha Bakery. Made of eight round bead-like segments all topped with a signature glaze, the doughnut conceals a bright purple interior that makes it nearly as beautiful as it is delicious.

In this university town with a student-to-resident ratio of six to one, junk food reigns. To make Shepherdstown Sweet Shop Bakery's Sweet Heat, a shell doughnut is filled with peanut butter mousse, then iced with chocolate and topped with roasted chopped peanuts and Route 11 Mama Zuma’s Revenge Jalapeño Potato Chips. “After each bite the richness of peanut butter and chocolate is subtly replaced by the heat of the chips for a unique eating experience,” says owner Pamela Berry.

A fritter is basically any kind of fried patty of deliciousness. Located in Wells, Congdon’s Doughnuts has been baking for 61 years, and the apple fritter has become the top-selling sweet in the glass case. Cinnamon and chunks of apple are mixed into dough, which is hand-cut, fried and topped with glaze. Fritter fanatics can also partake in versions full of juicy Maine blueberries or bacon-studded maple too.

Need a birthday or thank-you gift? Skip the cards and flowers and order these custom edible letters from Flyboy Donuts in Sioux Falls. They can be spread with any number of flavored glazes, then topped with candies, crushed cookies or colored sprinkles. Y-E-S, please.

Whimsical or terrifying depending on your perception, the Louie at The Donut Whole is a tribute to an automaton who played a turn-of-the-century band organ at the gates of defunct Wichita amusement park Joyland. The from-scratch buttermilk cake doughnut is dipped in cream cheese glaze, decorated with a blue buttercream ruffle and harlequin sprinkles, and topped with a jumbo cherry red gumball “nose.”

Pastry Chef Allison Smith’s mother, who loves to indulge in a glass of red wine with cheese and fruit, jokingly suggested creating a doughnut at Glazed Gourmet Doughnuts in Charleston that uses all three. Smith accepted the challenge, filling a doughnut with fresh pear compote and blue cheese, then topping it with a Cabernet Sauvignon-based glaze and a drizzle of honey. It would be equally enticing at breakfast or a tony cocktail party.

Made from a classic brioche recipe that originated in the South of France, using sustainable bread flour, cage-free eggs, hormone-free whole milk and European-style butter, this doughnut is great to begin with. To make it destination-worthy, Blue Star Donuts’ staff fills it with creamy vanilla custard, torch-fires sugar to brulee the top, then serves it with a squeeze-your-own pipette of Cointreau, orange zest and pure vanilla paste for a sweet citrus flavor.

A penchant for spicy Thai food stirred Short Lease Hotdogs + Rollover Doughnuts' owners Brad and Kat Moore to bake up a pastry treat that encompasses the colors and flavors of their favorite Southeast Asian cuisine. A hand-rolled brioche doughnut is filled with a chile pepper-tinged coconut custard and topped with coconut icing and toasted coconut flakes. Lip-tingling with the right amount of burn, this doughnut is the perfect example of sweet heat meets breakfast treat.

Launched in 2006 in North Carolina’s Outer Banks, Duck Donuts now has 26 locations. The popular Maple Bacon version starts with one of the shop's signature vanilla cake doughnuts. It’s topped with a salty-sweet duo of maple syrup and bacon, leading to a creamy and smoky tantalizing blend of tastes and textures. To say it inspires a devoted following is an understatement: One couple even got engaged over the warm and made-to-order pastry.

The three locations of Sweetwater’s Donut Mill are open 24 hours a day, seven days a week. That’s a good thing, as the Cheesecake Doughnut practically flies off the shelves. An ode to the Big Apple’s most-well-known dessert, it’s a yeast bismarck doughnut filled with tangy cream cheese filling and topped with bright-pink strawberry cream icing — both made using Sweetwater’s in-house recipes.

Inspired by the classic Cuban baked puff pastry filled with sweet or savory toppings, the Pastelito is a doughnut covered in cream cheese glaze with a guava glaze, available at the six Philly-area locations of Federal Donuts. It's a tropical, exotic treat just like you'd find on food carts in Havana.

The shop assistant’s family owns an Italian cheese shop in East Haven, so a subtly sweet doughnut riff on the classic ricotta cheese-filled cookie shell was the perfect way to represent a bit of the boot. The original name for it was actually the Mambo Italiano; either way, it’s enjoyed by all who crave that classic Italian dessert, even at breakfast.

It would be a pretty massive omission if Key West’s first doughnut shop didn’t offer an homage to the region’s most-famous dessert. To create Glazed Donuts’ Key Lime rendition, a yeast doughnut is filled with housemade Key lime curd, topped with bruleed meringue and sprinkled with graham cracker streusel. Owners Jonathan and Megan Pidgeon admit it’s messy to eat, making it hilarious for newcomers to watch.

When can you nosh on a doughnut for lunch sans guilt? When it’s this salty, sweet, smoky and creamy take on the French sandwich the Croque Monsieur. To create it, Revolution Doughnuts' chefs slice a pillowy yeast doughnut in half lengthwise, spreads it with housemade bechamel sauce, fills it with a slice of black forest ham, tops it with Gruyère cheese, and bakes it until it's gooey and crunchy. Mais oui!

A Hawaiian-themed doughnut shop in the middle of Des Moines makes perfect sense at Mahalo’s Coffee & Mini Donuts. The owners were inspired by their love of the Hawaiian Islands and the "aloha spirit," and they love dishing with customers about their experiences in our 50th state. Named for a popular resort on Oahu, the miniature Turtle Bay cake doughnut is topped with chocolate and caramel glazes and crushed pecans, just like turtle candy.

Fastnacht is German for “night before the fast,” and it’s a tradition to eat deep-fried, sugar-covered Fastnacht doughnuts the day before Lent starts. Krumpe’s Do-Nuts in Hagerstown has been selling them for 75 years. The day before Lent isn’t the only celebration: On Dec. 31 a giant doughnut is even dropped from the clock tower on the square, and doughnuts, coffee and hot chocolate are doled out to help ring in the new year.

The exotic flavors of this mango-glazed doughnut are one example of Owner Lisa Clark’s mission to make amazing raised doughnuts (assisted by her pastry-enthused children). Mojo Monkey Donuts’ signature yeast dough (crafted with locally brewed beer, yams and parsnips) is made into a ring, then topped with organic mango glaze and unsweetened coconut for a tropically inspired treat.

After Hurricane Katrina struck in 2005, there was a desperate need for supplies to keep local Mississippi businesses running in hard-hit areas. Staff of The Tatonut Donut Shop in Ocean Springs decided to take the irregular edges of dough that were typically discarded and fry them instead. The results, called Katrina Pieces, were such a hit that they ended up staying on the regular menu even after supplies were back to normal.

At first glance, this doughnut seems pretty simple, but owner Julie Goodnight points out that it’s entirely handmade — including the glaze. The result is amazingly large and fluffy, with just the right amount of sweetness and a perfect texture. It also brings in the regulars in droves; patrons come for the doughnuts and stay for the coffee and convivial conversation.

Named for owners’ Joe and Kristin Thomas’ friend’s teenage son, David, who frequently suggested new doughnut flavors to create — mostly involving alcohol and quickly shot down — the Dirty Dave is the result of his first great idea. The Dirty Dozen Donut Shop's offering is spread with peanut butter and topped with crumbled Oreos. The duo loved the delicious results, and the cookie concoction remains one of the shop's top sellers.

Inspired by owner Younts Waters’ mom’s apple pie, Strong Pump Hands at Polar Donuts are kind of like bear claws, but they have a bit more of an irreverent connotation. The glazed, four fingered doughnuts are filled with apple chunks and cinnamon, and they are among the most-popular (not to mention talked-about and Instagram-worthy) options on the menu of a shop that’s been on the Oklahoma City scene for more than two decades.

Pie becomes portable with the genius Pie Doughnut at The Doughnut Hole in Lincoln. The shop started as a farmers market stand and combines traditional, classic flavors with modern flair. The unique, fresh and eye-appealing creations include those filled with blackberry, peach, blueberry or apple, topped with crumbles and drizzled with icing.

Dead rock stars — including Elvis — make their appearance on several doughnuts at Stonehouse Baking Company. But Owner Denis St. Pierre pays homage to Purple Haze, the signature song of the Seattle-born legend Jimi Hendrix with a homemade vanilla cake doughnut topped with black raspberry icing.

Owner Sandy Ostlund shows his pride for the North Dakota State University football team, the Bisons, by making doughnuts just for tailgating. The Bison Pride doughnuts are topped with green and yellow frosting — the school’s colors. Sandy’s also makes the Horns Up, which is shaped as the hand gesture fans make to cheer their team. On game weekends, the shop sells upward of 10,000 per day.

Known as the Buckeye State, Ohio has a namesake nut that grows from a native tree indigenous to the state. The nut inspired a lookalike treat of peanut butter balls dipped in chocolate, which inspired Buckeye Donuts in Columbus. Filled with peanut butter and dunked in chocolate, the Buckeye Donut has been served since the shop opened its doors in 1969.

For those who haven’t tried Rhode Island’s beloved coffee milk, imagine drinking sweet, creamy coffee ice cream that’s been melted down. The supersized Coffee Milk doughnut, which is about three times the size of the standard one, is a buttery brioche-dough base covered in a coffee-milk glaze made with beans from Dave’s Coffee. Chocolate espresso beans are the final garnish.

Before opening their Boise shop, married couple Angel and Kevin Moran sold doughnuts at farmers' markets; today, they still glean inspiration from market stalls, using locally grown fruit for creations like the raised vegan blood orange-basil doughnut. Tart, freshly squeezed blood orange juice gets a sprinkle of cardamom and a punch of local basil for the sweet housemade glaze.

A staple on the Salt Lake City culinary scene for the past 30 years, Banbury Cross Donuts keeps locals and visitors alike sugar-fueled with cake doughnuts, bismarcks and buttermilk bars. Their best-selling coffee cake-hybrid offering is fried, then immediately dipped into a glaze and then cinnamon sugar for a two-for-one morning treat.

Named for the fan who submitted this flavor suggestion, which was inspired by strawberry cheesecake, the Scholbe the Cheesecake has become one of Holey Moley’s favorite doughnuts. A yeast doughnut is filled with housemade strawberry (and sometimes raspberry) jam, covered with cheesecake topping, dusted with graham cracker crust and finished with another dollop of jam on top.

Named for owner Jeanine Keppel’s dog, this Anchorage shop — opened in 1985 — has quite a loyal local following. Out of the 50 varieties of fluffy, fresh and delightful offerings, it’s the signature doughnut that’s most popular with toddlers and the school-age set (kids and dog lovers of all ages, really.) As its name suggests, the Dino Bone is worked into the shape of a canine treat and covered with a vanilla glaze.

While studying abroad in London, Heavenly Donut Company co-owner Kimberly Beiersdoerfer fell in love with the creamy, nutty goodness of that ultimate toast topper Nutella. Her creation, a bismarck doughnut filled with light and fluffy chocolate hazelnut cream, pays homage to the land across the pond. And it’s only available on Fridays, making it that much more covet-worthy.

When Red Hen Baking Co. was looking for a way to use the scraps of dough trimmed off during the croissant-making process, the staff discovered that rolling out, cutting and baking squares to toss in cinnamon sugar made for a treat that tasted remarkably like doughnuts. Owner Randall George says they make a great little inexpensive treat, but suggests you snatch 'em up when you can, as they are in limited supply depending on how many batches of croissants they are making.

Out of the 55 unique varieties of doughnuts and kolaches made in this Rock Springs bakery each day, the confection-inspired Turtle doughnut often sells out most quickly. A freshly made doughnut is covered with homemade chocolate fudge icing, topped with cinnamon candied pecans and finished with housemade caramel. Sweet tooths: Think outside the candy box.