Funfetti Cake

• 1 ⅔ cups all-purpose flour
• ¼ teaspoon baking soda
• 1 teaspoon baking powder
• 1 cup granulated sugar
• ¼ teaspoon kosher salt
• 3 egg white
• ½ cup sour cream
• ½ cup milk
• 3 teaspoons vanilla extract
• ¾ cup unsalted butter
• ⅓ cup jimmies sprinkles
• 1 lb unsalted butter
• 2 lb confectioners sugar
• 1 teaspoon vanilla extract
• 1 teaspoon milk
• 1 soft pink gel food coloring
• ¼ cup jimmies sprinkles
• 5 egg white
• 2 dashes cream of tartar
• 1 dash kosher salt
• 1 cup granulated sugar
• ⅓ cup granulated sugar
• ⅓ cup granulated sugar
• 2 teaspoons vanilla extract
• 1 lb unsalted butter, 1 tablespoon at a time
• ½ cup candy melts
• 2 tablespoons white chocolate chips
• 3 tablespoons heavy whipping cream

Preparation

1. Step 1

   0:12
   Sift the all-purpose flour, baking soda, baking powder, granulated sugar, and kosher salt into a large bowl. Whisk to combine.
2. Step 2

   0:36
   Separate three egg whites from the yolks (yolks not used). Add the egg whites, sour cream, milk, and vanilla extract to a bowl and whisk together. Add the room-temperature unsalted butter and mix until combined (it may look clumpy like cottage cheese).
3. Step 3

   1:25
   Add the dry ingredients to the wet ingredients and mix until combined. Fold in the jimmies sprinkles, being careful not to overmix.
4. Step 4

   2:18
   Butter and flour three 6-inch cake pans. Add baking strips to the pans if using. Evenly divide the batter between the prepared pans.
5. Step 5

   2:55
   Bake at 340°F until the centers are set and the edges are just pulling away from the pan, about 30 minutes.
6. Step 6

   3:35
   For the vanilla buttercream, mix the room-temperature unsalted butter on low speed for about 5 minutes until creamy and silky. Sift in the confectioners sugar in two batches, mixing on low after each addition (cover with a tea towel to prevent mess). Add the vanilla extract and a teaspoon of milk and mix until the desired consistency is reached.
7. Step 7

   4:27
   Divide the vanilla buttercream into two batches. Color one batch with one drop of soft pink gel food coloring. Add a quarter cup of jimmies sprinkles to each batch and fold in gently.
8. Step 8

   5:46
   For the Italian meringue buttercream, combine the water and granulated sugar in a saucepan. Heat over medium-high until it reaches 240°F. Meanwhile, whip the room-temperature egg whites with cream of tartar and a dash of salt until frothy. Add a third cup of sugar and continue whipping to soft peaks. Slowly drizzle in the hot sugar syrup while mixing on low, then mix on high until the meringue reaches room temperature (about 15 minutes). Add vanilla extract, switch to a paddle attachment, and add the butter a tablespoon at a time until the buttercream comes together.
9. Step 9

   7:25
   For the pink ganache drip, chop the candy melts and combine with the mini white chocolate chips in a bowl. Heat the heavy whipping cream until scalding and pour over the chocolate mixture. Let sit to melt, stirring until smooth. Add a small amount of soft pink gel food coloring and mix.
10. Step 10

    8:14
    Place the first cake layer on a board. Pipe and spread a layer of the funfetti vanilla buttercream on top. Stack the next layer and repeat, alternating buttercream colors if desired. Apply a thin crumb coat of buttercream to the outside of the cake. Chill to firm. Apply the Italian meringue buttercream to the outside of the cake and smooth with an offset spatula and bench scraper. Press sprinkles onto the bottom edge of the cake by hand. Pipe the warm pink ganache on top of the cake and smooth. Pipe dollops of Italian meringue buttercream on top using a large star tip.