Root Beer Float Cake with Root Beer White Fluff Icing

★★★★★ 3 Reviews
mooers51 avatar
By Denise Regan
from Mauldin, SC

This one of my daughters favorite cakes. Its the perfect taste for a summer sweet. There is usually none left!

Blue Ribbon Recipe

The frosting of this root beer cake is the star of the show. It's fluffy like the foam on a mug of root beer and has the same amazing flavor. It almost fizzes in your mouth. The cake is moist, delicious, and pairs well with the frosting. Have fun with decorating... drizzle with chocolate, top with cherries and serve slices with a mug of root beer. This is a really cool and delicious cake recipe.

— The Test Kitchen @kitchencrew
serves 10-12
prep time 20 Min
cook time 1 Hr
method Bake


  • CAKE
  • 1 box
    white cake mix
  • 3
  • 1/2 c
    sour cream
  • 1 c
    root beer
  • 1 tsp
    root beer concentrate
  • 1/2 tsp
  • 1/2 c
  • 3 Tbsp
  • 3 Tbsp
    white corn syrup
  • 2/3 c
  • 2
    egg whites
  • 3/4 tsp
    root beer concentrate
  • 1 tsp

How To Make

  • 1
    Preheat oven to 350 degrees and gather ingredients.
  • 2
    Mix cake mix with 6 remaining ingredients.
  • 3
    Pour into a greased and floured Bundt cake pan.
  • 4
    Bake for 50 min.
  • 5
    Let cool.
  • 6
    FOR ICING: Bring water, white corn syrup, and sugar to a boil and cook until 235 or the sugar syrup threads. Begin to test the syrup at 225.
  • 7
    Take a spoonful of the syrup and dip the spoon in a bowl of cold water. Tip the spoon to see if it releases a thin thread of syrup. If it threads, it's ready to take off the heat. If it drips instead of threading it needs to boil a little more. You want the sugar syrup to spin a 6-8 inch thread.
  • 8
    As soon as the sugar syrup starts boiling, start beating egg whites on medium speed. When the syrup threads, remove it from the heat. Turn the mixer to high speed and pour a thin stream of the syrup into the beating egg whites.
  • 9
    Beat continually until frosting is stiff and glossy. Add vanilla and root beer concentrate.
  • 10
    Continue to beat until mixed well.
  • 11
    Spread on cooled cake.