Overhead image of a slice of root beer float cake topped with vanilla ice cream on a white plate with a spoon and the frosted cake in the background.

Root beer floats. Cake. Root beer float cake. Totally genius. And so delicious.

I adore root beer floats. Actually, floats of any kind. I have been known to throw a scoop of vanilla ice cream in a bowl and pour Diet Coke over it. There are many things I am not above doing all in the name of getting a sweet fix. Remember a few years ago when Wendy’s introduced their Frosty Floats? At the time I lived less than half a mile from a Wendy’s and made an embarrassing number of drive-thru runs that summer for those floats. It’s so much better to make a root beer float cake in the privacy of your own home and enjoy it without perceived judgement. Unless you’re judging yourself. For licking a wee bit too much of the “leftover” frosting out of the bowl. And giving yourself a stomachache. When you were supposed to be sticking to fruits, vegetables and grains. Oops. It’s not really my fault. The frosting cast some sort of addicting spell…

Root beer in a glass measuring cup.

Given my love for root beer floats, you’d think I could remember the last time I actually had one, but I can’t. Which made finishing the bottle of leftover root beer so, so glorious. Ahh, sweet bubbly.

A serving of root beer float cake on a white plate with a spoon topped with vanilla ice cream.

There is a whopping 2 cups of root beer used in the batter for this cake, and another ¼ cup is used in the frosting, so you definitely get the root beer flavor. Plus, the cake sort of soaks in the flavors the longer it sits. If you bake the cake, cool it and then wrap it well in plastic wrap and serve it the next day, the root beer flavor will have intensified.

Root beer float cake batter in a Bundt pan before baking.

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After having made Guinness chocolate cupcakes and Guinness chocolate ice cream for St. Patrick’s Day, it should have dawned on me that if a deep velvety beer was a great pair with chocolate, then it stood to reason that root beer would be as well. It has the same type of complementary effect – it brings out the depth and richness of the chocolate, while imparting its own unique flavor. Quite simply, it’s awesome. And the frosting is so far out of this world insanely good, I have no other words. You just have to make it. You have to.

Overhead image of root beer float cake on a cooling rack.

The other thing you have to do is serve this cake with vanilla ice cream. Aside from the obvious float connotation, the ice cream complements this cake perfectly. It is a very rich cake, and the cool smoothness of the ice cream helps to balance it out. Also, there is a reason there are two scoops of ice cream in the pictures (even though one would have made for a better picture). You simply need two scoops. One won’t cut it. Trust me.

A serving of root beer float cake on a white plate with a spoon topped with vanilla ice cream.

I’m pretty sure that this is the perfect summer dessert. Going to a picnic or graduation party and need to bring something? (Perhaps even this weekend for Memorial Day?) This is your new secret weapon. Everyone will love you and want the recipe. And the kicker? You don’t need a mixer of any sort for this cake. A saucepan and three bowls for everything (including the frosting). This really is a magical cake. And it’s a bundt cake. Which is all sorts of retro chic right now. Which I happen to love.

P.S. The leftover root beer and vanilla ice cream? Homemade root beer floats, woo!

A bottle of root beer and a pint of vanilla ice cream.

One year ago: Blackberry Pie Bars
Two years ago: Greek Celebration Bread – Christopsomos
Three years ago: Buttermilk Pancakes

Overhead image of a slice of root beer float cake topped with vanilla ice cream on a white plate with a spoon.

Root Beer Float Cake

Yield: 12 servings (One 10-inch bundt cake)
Prep Time: 30 minutes
Cook Time: 40 minutes
Total Time: 1 hour 10 minutes
A delicious cake inspired by a root beer float
4.50 (4 ratings)
Print Pin Rate

Ingredients

For the Root Beer Bundt Cake:

  • 2 cups (472 ml) root beer, do not use diet root beer
  • 1 cup (86 g) dark unsweetened cocoa powder
  • ½ cup (113.5 g) unsalted butter, cut into 1-inch pieces, (4 ounces )
  • 1¼ cups (250 g) granulated sugar
  • ½ cup (110 g) dark brown sugar
  • 2 cups (250 g) all-purpose flour
  • 1¼ teaspoons (1.25 teaspoons) baking soda
  • 1 teaspoon salt
  • 2 eggs

For the Root Beer Fudge Frosting:

  • 2 ounces (56.7 g) dark chocolate, melted and cooled slightly
  • ½ cup (113.5 g) unsalted butter, softened, (4 ounces )
  • 1 teaspoon salt
  • ¼ cup (59 ml) root beer
  • ⅔ cup (57.33 g) dark unsweetened cocoa powder
  • 2½ cups (300 g) powdered sugar

Instructions 

  • 1. Preheat oven to 325 degrees F*. Generously spray the inside of a 10-inch bundt pan with nonstick cooking spray, or butter the pan and dust with flour, shaking out the excess flour; set aside.
  • 2. In a medium saucepan, heat the root beer, cocoa powder and butter over medium heat until the butter is melted. Add the sugars and whisk until dissolved. Remove from the heat and let cool.
  • 3. In a medium bowl, whisk the flour, baking soda and salt together.
  • 4. In a small bowl, whisk the eggs until just beaten, then whisk them into the cooled cocoa mixture until combined. Gently fold the flour mixture into the cocoa mixture. The batter will be slightly lumpy, which is okay. Do not overbeat it, as it could cause the cake to be tough.
  • 5. Pour the batter into the prepared pan and bake for 35 to 40 minutes, rotating the pan halfway through the baking time, until a small sharp knife inserted into the cake comes out clean. Transfer the pan to a wire rack to cool completely. Gently loosen the sides of the cake from the pan and turn it out onto the rack.
  • 6. To make the Root Beer Fudge Frosting, put all of the ingredients in a food processor. Pulse in short bursts until the frosting is shiny and satiny, scraping the sides of the food processor a couple of times. (If you don't have a food processor, simply throw it all into the bowl of a stand mixer or a large bowl using a hand mixer and mix on medium-low until combined and satiny smooth.)
  • 7. Use a spatula to spread the fudge frosting over the cake in a thick layer. Let the frosting set before serving. Store leftovers wrapped well or in an airtight container at room temperature.
  • *Note: If you are using a dark, nonstick pan, heat the oven to 300 degrees F.
Calories: 508kcal, Carbohydrates: 84g, Protein: 5g, Fat: 19g, Saturated Fat: 12g, Cholesterol: 68mg, Sodium: 526mg, Potassium: 260mg, Fiber: 5g, Sugar: 60g, Vitamin A: 510IU, Calcium: 40mg, Iron: 3.4mg

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Author: Michelle Lettrich
Course: Dessert
Cuisine: American