The average high in Austin this time of year is 97 degrees, so it's no wonder the city's ice cream festival was an instant hit when it started in 2007. Nearly 12,000 people showed up that summer, and now the all-day event ( taking place August 4, $10; www.icecreamfestival.org) is an annual affair, with an ice cream eating contest, Popsicle-stick sculpting and, most important, an ice cream making competition. It's an intense battle: Contestants have to bring their own machine and churn out their creation on-site for a panel of four locals and four discerning kids. We asked champions from past festivals to hand over their winning recipes.

Every year on the Fourth of July, Laura Duckworth's family hosts its own ice cream competition. So when the second-grade teacher heard about her city's first-ever ice cream festival in 2007, she knew she had to enter the ice cream contest. She used the same strawberry soda recipe that won her family's 1950s-themed competition a month earlier and walked away with the championship trophy — a giant spoon.

Amy Huff didn't think there was any way she'd win the contest when she entered in 2008: "Everyone else showed up with hot plates and slow cookers," the accountant says. "They spent hours getting their recipes ready, whereas I was done in five minutes." Huff's simple Red Hots candy-inspired flavor beat out more involved ones like pina colada and honey almond. "I wasn't expecting it," she says, "but I'll gladly take the bragging rights."

Contest rules don't ban food professionals from competing at the Austin Ice Cream Festival, so Bob Blumer, host of Food Network Canada's Glutton for Punishment, decided to enter in 2009 — even though he'd never churned out his own ice cream. After getting a crash course from local ice cream shop owners, Blumer created a winning combination: maple syrup and bacon. "Now everyone's doing bacon-maple this and bacon-maple that," Blumer says, "but at the time, it was at the forefront of the movement."

When Collin Hazlett signed up for last year's competition, he planned to enter the peach flavor that his family always makes after their annual peach picking. But then Hazlett, a math major at the University of Texas at Austin, started having second thoughts: Peach ice cream is standard in most supermarkets. Luckily, Hazlett's dad had held on to a clipping for Milky Way ice cream from a 1984 edition of the Austin American-Statesman, so he made that instead. "Since there were kids judging," he says, "I thought I had a pretty good shot."