The Best Yellow Cake I’ve Ever Had

Soft and buttery with an extra moist crumb this is the best yellow cake Ive ever had. After several rounds of recipe testing I found the secret to the most delicious yellow birthday cake is a combination of cake flour extra egg yolks whipped egg whites and buttermilk. Cover this cake with my rich and creamy chocolate buttercream for the ultimate celebratory birthday cake!
Ingredients
2 and 1/2 cups 285g cake flour spooned leveled
2 and 1/2 teaspoons baking powder
1/4 teaspoon baking soda

1/2 teaspoon salt
1 cup 2 sticks 230g unsalted butter softened to room temperature
1 and 3/4 cups 350g granulated sugar
4 large egg yolks room temperature
2 teaspoons pure vanilla extract
1 cup 240ml buttermilk at room temperature
2 large egg whites room temperature
1/8 teaspoon cream of tartar
Chocolate Buttercream
1.25 cups 2.5 sticks or 290g unsalted butter softened to room temperature
3 and 1/2 cups 420g confectioners sugar
3/4 cup 65g unsweetened cocoa powder natural or dutch process
3-5 Tablespoons 45-75ml heavy cream or halfandhalf or milk at room temperature
1/4 teaspoon salt
1 teaspoon pure vanilla extract
optional for decoration sprinkles
Instructions
Preheat oven to 350F 177C. Grease two 9inch round cake pans line with parchment paper rounds then grease the parchment paper. Parchment paper helps the cakes seamlessly release from the pans. If its helpful see this parchment paper rounds for cakes video post. I recommend using nonstick spray for greasing.
Start the cake batter with the dry ingredients Whisk the cake flour baking powder baking soda and salt together in a large bowl. Set aside.
Using a handheld or stand mixer fitted with a paddle attachment beat the butter and sugar together on high speed for 3 full minutes. The creamed butter and sugar will be extra creamy. Scrape down the sides and up the bottom of the bowl with a rubber spatula as needed. Turn the mixer down to mediumhigh speed and beat in the 4 egg yolks one at a time letting each egg yolk fully mix into the batter before adding the next. Beat in the vanilla extract until combined.
Add about 1/3 of the dry ingredients and 1/2 of the buttermilk and beat on low speed until combined. Add 1/3 more of the dry ingredients and the rest of the buttermilk and beat on low speed until combined. Add the rest of the dry ingredients and beat on low speed until combined. The batter is very thick. You may need to whisk it all by hand to make sure