America's Best Fast Food Shakes (Slideshow)

The popular chain makes its own addictive style of soft serve called Icedream, and offers four regular flavors: chocolate, strawberry, cookies and cream, and vanilla. However, it's the peach shake they offer in the summertime that lands them on this list. The peaches are a nod to the company's Georgia roots, and this sweet warm weather treat is a favorite in the South.

DQ's founders invented soft serve, so it's no wonder that their soft serve shakes are the perfect balance of creamy and thick. Plus their shakes come in decadent flavors like caramel cheesecake and Oreo — in case you need an extra incentive to give in to temptation. 

On its own, Freddy's frozen custard is habit-forming. Blending chocolate or vanilla custard with milk for a drinkable dessert is downright dangerous. 

The Frosty is legendary, and nearly a milkshake by itself, but did you know that Frosty shakes come in chocolate fudge, caramel, and strawberry flavors? Proof that even a classic can be improved upon.  

The Habit Burger is the best chain that no one has ever heard of, but that might be about to change. The California chain was recently named Best Burger in America by Consumer Reports, toppling reigning champ In-N-Out, and there are almost as many rave Yelp reviews about their thick-enough-to-need-a-spoon shakes as there are about the burgers.

This San Francisco Bay area chain serves fast food with a conscience, and their shakes are a testament to their commitment to quality food. Each shake is made with Straus organic soft serve, which contains simple ingredients and no thickeners, additives, or artificial colors. 

It's no surprise that the company that bills itself as "America's drive-in" offers a huge spectrum of shakes from standard to slightly offbeat fare, like lemon pie and pineapple, to completely bizarre flavors you'd never think to mix up — stop in and try a chocolate jalapeño shake if you find yourself sick of plain-Jane vanilla.

When you've got the word "shake" right in your moniker, you'd better deliver, and Steak and Shake does. Their shakes are thick and creamy like a good milkshake should be, but they land on this list for sheer audacity. With flavors like birthday cake, Snickers, and chocolate-covered strawberry, who needs the steak? Just bring on the shake. 

This Northeastern chain hand spins its custard daily, and the shakes are all the better for it. Plus, in addition to the standard strawberry, vanilla, and chocolate, you can get caramel or peanut butter. They're so good locals find themselves craving a Shake Shack fix even in the dead of winter.

Hey, it's hard to argue with celebrity chef Alton Brown, who voted In-N-Out Esquire's best fast food spot in America, raving "the shake tastes the way shakes tasted back when I was a kid. It makes me tear up just thinkin' about it."