Sprinkle Cake

• 4 1/2 cups (540g) cake flour*
• 4 1/2 teaspoons baking powder
• 1 1/2 teaspoon kosher salt (I use Diamond Kosher)
• 9 large (270g) egg whites, room temperature
• 3 tablespoons (36g) granulated white sugar (for meringue 🥚)
• 9 tablespoons (126g) unsalted butter, slightly softened
• 2 cups (399g) granulated white sugar (for butter 🧈)
• 9 tablespoons (111g) oil (flavorless such as canola or veg)
• 3 teaspoons vanilla extract (real or imitation)
• 1/2 teaspoon (3g) almond extract (optional)
• 1 1/2 cups (366g) buttermilk (any fat content), room temperature
• 12 tablespoons sprinkles**

Vanilla American Dreamy Buttercream

• 3 3/4 cups (850g) unsalted butter, softened slightly
• 1 2/3 cups (520g) light corn syrup**
• 3 1/8 cups (352g) powdered sugar (unsifted ok)***
• 1/4 teaspoon salt (to taste, start with a pinch)
• 2 1/2 teaspoons vanilla extract

Bake the cake:

1. Move your oven rack to the middle position. Preheat the oven to 350°F.
2. Butter the insides of three 8” cake pans and line the bottoms with a circle of parchment paper. Dust a very light coating of flour inside the pans.
3. Sift cake flour and baking powder into a bowl. Whisk the kosher salt in a large bowl for at least 30 seconds to distribute the baking powder evenly.
4. Let’s prep the meringue. To your mixing bowl, add the egg whites. Pour the white granulated sugar (labeled “for meringue 🥚") into a small bowl so it’s easy to add to the egg whites while mixing.
   
   With a hand or stand mixer and the whisk attachment, beat on medium-high speed until it’s thicker with large bubbles. It will look like really sudsy dishwater. Pour in about 1/2 tsp of sugar, continue to whisk, and then pour another 1/2 teaspoon. No need to be precise on the amount of sugar, but wait about 5-10 seconds between additions to allow the sugar to dissolve a little before adding more.
   
   Once all the sugar has been added, continue to whisk until you reach stiff and glossy peaks. When you pull up some meringue with the whisk attachment, you should see a point that bends just a little when you hold it upside down, and it shouldn’t be runny or drooping off the whisk.
   
   Pour the meringue into a small bowl and set that aside for now. (No need to clean this bowl, we’ll use it to make the rest of the batter.)
5. In that same meringue mixing bowl and with a paddle attachment, beat the softened butter and sugar (labeled “for butter 🧈") on medium-high for about 3-5 minutes until lighter in color and fluffier. Add the oil, vanilla, and almond extracts and beat for another 2 minutes. It should turn whiter in color or more tan, depending on the potency of your vanilla extract. Scrape down the bowl.
6. We will now alternate adding the flour mixture and buttermilk. Add the flour in 3 additions and the buttermilk in 2 additions as follows:
   
   Add half of your flour mixture to the butter-sugar bowl. On low speed, mix until all the flour has just been incorporated. Scrape down with a spatula.
   Add in half of your buttermilk, mix on low speed and scrape.
   Next, add half of your remaining flour mixture, mix on low speed and scrape.
   Add the rest of your buttermilk, mix on low, and scrape. Finish with the rest of the flour, mix on low, and scrape.
7. Take 1/2 of your meringue and fold it into the cake batter with a spatula. Use swooping motions to scoop the batter from the sides and pile it towards the center. Make sure you scrape the bottom of the bowl once in a while. Once all the batter contains no more streaks of meringue, add the second half plus the sprinkles and continue to fold. It’s essential to ensure that the batter is thoroughly combined with the eggs, or you may get an uneven rise in the final cake. (This is usually more apparent in the larger 6 or 8” cakes but less with cupcakes.) The batter should not have any lines of meringue, be tan or cream in color with evenly dispersed sprinkles throughout, and be slightly more voluminous.
8. Evenly distribute the batter into the prepared pans.
9. Bake for about 35-40 mins or until a skewer inserted in the center comes out with a few crumbs attached. (Start around 30 mins.) If you do not have three pans, you can bake them one after another. Let the batter sit out at room temperature until you’re ready to bake it.
10. Move the pans to a cooling rack and allow the cake to cool in the pans completely.
11. Loosen the edges of the cakes using an offset spatula or butter knife, and flip the cakes out onto a cooling rack so you can peel off the parchment bottom. Make sure they are completely cool before assembling and/or frosting.

Make the Frosting:

1. Add the softened butter to the bowl of your stand mixer. Using the whisk attachment, beat the butter on high speed until it's paler in color and slightly more voluminous.
2. Add the corn syrup in 3 to 5 additions. Stop the mixer, add a little bit first,  and mix it in at medium speed (still using the whisk attachment). Repeat until all the corn syrup has been added. Scrape down the bowl a couple of times to ensure everything is mixed well.
3. Once all the corn syrup has been added, mix at the highest speed for one minute.
4. Now give the frosting a taste. It should be smooth, creamy, and very buttery with a slight sweetness. This is to gauge how much powdered sugar to add in this step based on your preference. (Notice how glucose - the sugar used in corn syrup - is not as sweet as powdered sugar.)
5. Add the powdered sugar in a few additions, mixing on low speed to reduce the mess.
6. Once all the sugar has been added, mix on high speed for 30 seconds. Give it another taste. Do you want it sweeter or need a firmer consistency of buttercream?
7. You can stop here or add as much powdered sugar as you like. It can handle way more, but remember that the more you add, the sandier the finished frosting will be.
8. Now let's flavor and color the buttercream. Add the vanilla, a pinch of salt, and, optionally, a toothpick's end of purple food coloring (to achieve a whiter shade). Mix on high speed for another minute.
9. Switch over to a paddle attachment and run the frosting on low speed to get out any large air pockets. The finished buttercream will have minimal air bubbles and be ready to use.

Frost your cake as desired!

*Cake flour is best for this recipe. It’s more finely milled and has a lower protein than all-purpose flour. This translates to a more delicate and softer cake crumb. I use King Arthur Flour’s Unbleached Cake Flour, but the bleached versions will work just as well. I have made this recipe using all-purpose flour; it’s still delicious, but the cake’s interior will be a little more coarse.

**I use Karo light corn syrup, which is a syrup of sugars (glucose + maltose) derived from corn. The "light" is just an indication of the color of the syrup (not the sweetness.) You'll probably be able to substitute other syrups here if you like, but corn syrup is a flavorless option that allows us to customize this recipe for different flavors later on. If you do sub something else, know that corn syrup is less sweet than most other baking sugars. You'll likely have to use less than what I've written in this recipe here.

***This is a little over the maximum amount of sugar that will dissolve in the water contained in the butter. If you want less sweet buttercream, use less. If you want a stiffer consistency or sweeter buttercream, use more. Just know the more you add, the more grainy the finished buttercream will be. Don't worry, though; it will still be light years smoother than a traditional American buttercream.

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