Root Beer Float Layer Cake

If you have a root beer lover in your house or are looking for a great chocolate cake birthday cake for a birthday, then you'll love this Root Beer Float Layer Cake! With layers of root beer float cake and icing, this root beer cake tastes just like a classic root beer float, but even better because it's a cake! And it's the ultimate summer cake, birthday cake, or Father's Day Cake.

Chocolate cake, flavored with root beer extract, then painted in root beer syrup, making it super moist, with a light, fluffy, and not too sweet shortening (Crisco) based icing. This root beer cake is topped with marshmallow fluff to look like melted ice cream, with a cherry on top! If you are looking for birthday cake recipes, this is your cake! This root beer cake recipe pairs well with a summer meal such as Beef on a Bun and Slow Cooker New England Baked Beans.

🥘 Ingredient Notes

This cake is a chocolate cake made with root beer extract (You can buy the root beer extract HERE (affiliate link) through Amazon, because it's not easy to find), then it's painted with a reduced root beer syrup for the ultimate in root-beery flavor and moistness.

For this root beer cake, you'll need:

• Unsweetened cocoa. Adding cocoa gives this cake a chocolate flavor that boosts the root beer flavor.
• Root beer soda.It's critical that you don't use diet root beer for this recipe- I tried it and it doesn't work!
• Root beer extract. I prefer to use the concentrated root beer extract (shown below) because it gives you a potent root beer flavor without adding a lot of additional liquid that you need to worry about compensating for (specifically in the frosting). * I use 2 of these bottles for the cake and 1 for the frosting.

This Wilton whipped cream buttercream is a light and fluffy shortening-based icing that uses meringue powder (you can purchase Wilton Meringue Powder HERE (affiliate link) that isn't too sweet and is the best icing I have ever had!

I added the marshmallow fluff on top to make it look like the melting ice cream on a root beer float. This cake will take you a couple of hours. But trust me, the extra time is worth it. 

For this Root beer frosting, you'll need:

• Shortening. I generally use Crisco or Tenderflake. Using shortening makes for a nice, light and fluffy frosting that doesn't need refrigeration and stands up to the heat.
• Meringue powder. Meringue powder is a safe way of using egg whites (do NOT use egg whites for this recipe- you need this powder).
• Brown gel icing color. Make sure you are using a gel food coloring - grocery store food coloring will not work! I prefer to use Wilton brand or Americolor brand. You can buy them at craft/cake decorating stores or online.
• Marshmallow fluff or creme. You can use either, depending on which you can find more easily where you live. You can also order it online. *I used the creme.
• Maraschino cherries. You'll want to get maraschino cherries with stems, also known as cocktail cherries.
• Chocolate sprinkles. I use jimmies (they are the long, tube-like rod sprinkles), which are different from the round ones (non-pareils).

*See recipe card for full list of ingredients and quantities

📖 Variations & Substitutions

• Frosting: I use my Whipped Cream Buttercream Frosting for this cake, adding the root beer extract and brown food coloring. This frosting is a PERFECT pairing with this cake! It can be stored at room temperature for up to 2 months. When you go to use it again, it will need to be 'fluffed up/whipped with a spatula.
• Other frosting options: if you prefer more chocolate and less root beer in the frosting, you could use a different frosting, such as my 2-Ingredient White Chocolate Whipped Cream Frosting (Ganache) or my Chocolate Frosting (without butter).
• Cupcakes: ONLY brush the tops of the cupcakes with the root beer coating and bake for half the amount of time (about 15 minutes) or until cake tester comes out clean.
• Bundt cake: Pour batter into bundt cake pan and bake for 50 -60 minutes or until cake tester comes out clean.

🔪Step-by-Step: How to Make Root Beer Float Cake

PREP: Preheat the oven to 350 degrees F/175 degrees C. Grease three 8-inch cake pans and set aside (I use Wilton Cake Release).

MAKE THE CAKE (STEP 1 ): In the bowl of a stand mixer (with paddle attachment), combine flour, white granulated sugar, cocoa powder, baking powder, baking soda, and salt (IMAGE 1). Add eggs, milk, oil, and root beer extract to the flour mixture (IMAGE 2). Beat on medium speed for 2 minutes (IMAGE 3). Slowly stir in boiling water and continue mixing for another minute or until combined (IMAGE 4). 

BAKE THE CAKE (STEP 2): Pour cake batter evenly into 3- 8-inch prepared cake pans until each cake pan is ⅔ full. **Batter will be a little runny (IMAGE 5). Bake cake for about 30 minutes or until a cake tester comes out clean and/or the center of the top of the cake springs back when lightly touched (IMAGE 6). *You can use baking strips so your cakes bake more evenly, but I find them a pain, so I just level the cakes after they cool. Let cakes cool for 10 minutes before removing from pans to finish cooling on a wire rack (IMAGE 7).

MAKE THE ROOT BEER SYRUP (STEP 3): While cakes cool, pour root beer into a saucepan (IMAGE 8). Boil root beer in a heavy saucepan until reduced by half. It will form a syrupy liquid. (IMAGE 9).

LEVEL THE CAKE AND ADD THE SYRUP (STEP 4): Level the cakes (cut off the dome) with a sharp knife or cake leveler (IMAGE 10). Brush cakes with root beer syrup/concentrate (IMAGE 11). Once cool, cover in plastic wrap (or place in a sealed container) and refrigerate for several hours or overnight. **This is not critical, but you do get the best results if you do this. Alternatively, if you are short on time, you can leave it in the fridge while you make the frosting, then decorate it.

MAKE THE FROSTING (STEP 5 -PART 1): Put shortening in the bowl of a stand mixer and gradually add powdered sugar. Beat for about 5 minutes until the mixture is very creamy and fluffy. Set this aside. (IMAGE 12). In a very clean ,large bowl, mix dry ingredients (sugar, salt, and meringue powder). (IMAGE 13). Add BOILING water and immediately mix at high speed. Beat until stiff peaks form, about 8 minutes. When the mixture begins to get stiff, add root beer extract (IMAGE 14).

MAKE THE FROSTING (STEP 5- PART 2): Continue beating until combined (IMAGE 15). Combine both mixtures and beat together for another 8 minutes (IMAGE 16). The frosting will be very light and creamy. Add brown food coloring (IMAGE 17). Cover. DO NOT REFRIGERATE.

ASSEMBLE AND FILL THE CAKE (STEP 6): Transfer the first layer to a cake plate *If you have any holes or pieces that came off when you were removing the cakes from their pans, you can fix them with some frosting (to fill the gap or glue the piece back onto the cake) (IMAGE 18). Add frosting on top of the first layer of cake (IMAGE 19). Then add the second layer of cake and add frosting on top of that cake (IMAGE 20). Add the final layer cake (IMAGE 21).

FROST THE CAKE (STEP 7): Brush off any loose crumbs with a pastry brush. Then add a thick layer of frosting to the cake using a cake decorating spatula (use a separate bowl for frosting you are working with so crumbs don't get into the whole batch). You could also do a crumb coat, then refrigerate it for a few minutes -see expert tips (IMAGE 22). Spread from the thickest part of the frosting outwards, to avoid getting crumbs in the frosting, and smooth it as much as possible - it helps to heat the spatula in hot water and dry it before smoothing the cake (IMAGE 23). Then run a cake comb along the sides of the cake. (see sample method in video). (IMAGE 24).

DECORATE THE CAKE (STEP 8): Pipe a border on top and along the bottom with a #21 frosting tip (the top border is optional) (IMAGE 25). Then add a dollop of the marshmallow creme (or fluff), then a maraschino cherry in the centre, and sprinkle with chocolate sprinkles. I simply toss the chocolate sprinkles at the sides of the cake (IMAGE 26). I recommend serving this cake with vanilla ice cream for the ultimate root beer float experience! You can also add a dollop of marshmallow creme and a cherry to each piece of cake.

🎥 Video

Combing a cake: Combing a cake is a very simple decorating technique, and it works very well on this root beer cake. If you've never done it, then check out this video: How to ice and comb a cake *skip the refrigeration part, as this whipped buttercream should NOT be refrigerated!

Making a Border: A shell border is what you'll typically see used on cakes, using a #21 tip. I make a loose shell border. If you are not sure how to do a shell border, then check out this video: How to make a shell border with a #21 tip (it's the 3rd one)

👪 Serving Size

This root beer float cake recipe makes 1 - 8-inch 3-layer cake and serves about 14 people, depending on how large you cut the slices. However, you can half, double, or triple the recipe by clicking on the serving number and selecting the number of servings you'd like. The ingredient quantities will automatically adjust.

🥗What to Serve with Root Beer Cake

This Root Beer Cake is perfect for a summer birthday or summer celebration such as Father's Day! It goes well with summer meals such as Pulled Pork on a Bun, and Grilled Steak Salad ! (shown).

It also pairs exceptionally well with special birthday dinners such as this Baked Beef Cannelloni Recipe, or Make-Ahead Lasagna (with no boil noodles)

🌡️Storing

• Storing: Store this layer cake in an airtight container for up to 2 days at room temperature. Beyond that, it's best to freeze the leftovers.
• Freezing: Freeze leftovers in a sealed container for up to 3 months. You can also freeze this cake FULLY DECORATED, in a sealed extra large cake carrier (affiliate link) for up to 1 month. Defrost at room temperature.

❔ Recipe FAQs

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