Root Beer Float Cake

Slip on your saddle shoes and cue up the jukebox, because this root beer float cake is pure soda shop nostalgia in a 13×9-inch pan. Inspired by the classic root beer float, this cake bubbles with fizzy charm thanks to real root beer in both the batter and the frosting. It’s light and fluffy and just the right amount of kitschy, with a dreamy whipped topping that practically begs for a maraschino cherry on top.

Best of all? It starts with a trusty box of white cake mix, so you can whip it up faster than you can say “two straws, one shake.” Whether you’re throwing a retro-themed party, celebrating a birthday with the ultimate cake and ice cream combo, or just craving a taste of the good old days, this sweet slice of Americana is ready to serve.

Root Beer Float Cake Ingredients

• White cake mix
• Root beer
• Canola oil
• Eggs
• Whipped topping mix (such as Dream Whip)

Directions

Step 1: Mix the batter

Preheat the oven to 350°F. In a large bowl, combine the white cake mix, 1-1/4 cups of cold root beer, canola oil and eggs. Beat everything together on low speed for two minutes or stir vigorously by hand for three minutes until well combined.

Step 2: Bake the cake

Pour the batter into a greased 13×9-inch baking pan. Bake for 30 to 35 minutes, or until a toothpick inserted in the center comes out clean. Let the cake cool completely on a wire rack.

Step 3: Make the frosting and spread over the cake

In a small bowl, combine the whipped topping mix with the remaining 1/2 cup of root beer. Beat until soft peaks form—it should look light and fluffy.

Spread the frosting evenly over the cooled cake.

How to Store Root Beer Float Cake

Store the frosted cake in the refrigerator, loosely covered. It will keep for three to four days—after that, the whipped topping won’t be light and airy. You can also freeze individual slices for up to a month. Simply thaw them in the fridge before serving.

Root Beer Float Cake Tips

Can you use homemade whipped cream instead of Dream Whip?

It’s super simple to substitute homemade whipped cream for the whipped topping, but you’ll want to stabilize your whipped cream if you’re making the cake in advance. Add a little confectioners’ sugar or a stabilizer like instant pudding mix to help it hold up.

What kind of root beer works best in this cake?

Use a root beer with a bold, spicy profile like Barq’s or one of the best craft varieties made with real cane sugar. A regular, full-sugar root beer gives the best flavor and texture for both the cake and the frosting. Avoid diet sodas, as artificial sweeteners can affect the rise and taste. If you’re using a craft root beer, look for one with vanilla or wintergreen notes for extra flavor.

Can you make cupcakes instead of a sheet cake?

Absolutely! This batter also works well for cupcakes. Just divide it among lined muffin cups, filling them about two-thirds full, and bake at 350° for 15 to 20 minutes. Let cool completely before frosting.