Croissant Breakfast Casserole

Article by Kelly Vaughan

When you want to feed a crowd for the holidays without spending a ton of time in the kitchen, make this savory breakfast croissant casserole. With the texture of bread pudding and savory, salty flavors from a combination of bacon and fresh herbs, it’s a delicious way to kick off the day. And the best part is that it’s a make-ahead recipe, so you can prep it a day in advance, store it in the fridge, then bake it off just as your loved ones are getting out of bed.

How to Make Breakfast Croissant Casserole like a Pro

Prep the croissants. Use your favorite store-bought or bakery croissants to make this casserole. If you’re using fresh croissants, be sure to toast them before soaking to dry them out, which will make them more susceptible to absorbing the custard mixture. Alternatively, day-old or stale croissants work great and will save you the step of toasting fresh ones.

Make the filling. Start by cooking the bacon, then the onions until softened and translucent. Mix them together, cream cheese, herbs, scallions, nutmeg, cayenne pepper, Gruyère cheese, and Dijon to create a savory spread.

Assemble the casserole. Spread the bacon and onion cream cheese mixture between the halved, toasted croissants. Top with a savory custard mixture made from eggs, half-and-half, Dijon, salt, and black pepper. Let the assembled casserole soak overnight to ensure that there are no under-soaked dry spots after baking.

Bake and serve. Once the casserole has rested, bake it in a 325℉ oven for about 45 minutes until the egg custard is set and the croissants are golden brown.

Ingredient Swaps

Make it vegetarian. If cooking for a vegetarian crowd, the bacon can easily be swapped for cremini or shiitake mushrooms. Just sauté them in a bit of butter until tender and browned in spots.

Make it sweet. If you’re team sweet rather than team savory, you can omit the Dijon mustard from the custard and add ground cinnamon instead. Skip the bacon and herbs and fold in chopped dried fruit and nuts or chocolate chunks for the filling.

Change the bread. While the butteriness of the croissants adds a richness to the casserole, feel free to swap in any type of bread you have on hand.

How to Store Breakfast Croissant Casserole

To prevent this croissant casserole from becoming too soggy, be sure to let it cool completely before storing so it doesn’t steam.

Once it’s cooled, you can wrap the entire casserole in plastic wrap or foil and store it in the fridge for 3 to 5 days, or up to 3 months in the freezer.

To thaw, transfer the casserole to the refrigerator to defrost overnight. When ready to serve, bake, covered, at 350℉ until warmed through, then remove the foil and bake until the top is golden brown and crispy.

How to Serve Breakfast Croissant Casserole

This croissant breakfast casserole is best served straight from the oven while it’s still warm. To complete your breakfast or brunch spread, you can serve it alongside a fruity mimosa, a juicy fruit salad, or a refreshing fruit smoothie.

Breakfast Croissant Casserole FAQs

What are the ingredients for a Breakfast Croissant Casserole?

This savory casserole features a cream cheese filling studded with crispy bacon, sautéed onions, and herbs, but you could also make a sweet version with fresh or dried fruit, chocolate chips, and/or nuts. The staple ingredients include day-old croissants, plus eggs and half-and-half for the custard.