Cookie Crumble Cake

3 and 2/3 cups cake flour

1 tsp salt

2 tsps baking powder

3/4 tsp baking soda

2 cups granulated sugar

1 and 1/2 cups unsalted butter, softened

1 tbs vanilla extract

3 large eggs + 2 additional egg whites, room temperature*

1 and 1/2 cup buttermilk

32 milk chocolate chip cookies (12 roughly chopped, the rest whole)

1 and 1/2 cups unsalted butter, softened

5 - 6 cups powdered sugar

1/3 cup whole milk

1 1/2 tsps vanilla extract

1/8 teaspoon salt

Preheat oven to 350°F and grease three 9-inch cake pans, spray with non-stick spray and line with parchment paper.
Whisk cake flour, salt, baking powder, and baking soda together. Set aside.
Using a stand mixer fitted with the paddle attachment, beat butter and sugar together on high speed until smooth, about 2 minutes. Scrape down the sides and up the bottom of the bowl with a rubber spatula as needed and beat in the eggs, egg whites, and vanilla on high speed until well combined, about 2 minutes. (Mixture will look slightly lumpy) Scrape down the sides and up the bottom of the bowl as needed.
On low speed, add dry ingredients until combined. Add buttermilk and mix until combined.
Pour batter evenly into cake pans and bake for approximately 25 minutes or until the cakes are baked through. Let cool.
To make the frosting use a stand mixer fitted with a whisk or paddle attachment and beat the butter on medium speed until creamy, about 2 minutes. Turn to low and add powdered sugar, milk, vanilla, and salt. Increase to high speed and beat for 2 minutes.
Place 1 cake layer on your cake stand, and evenly cover the top with about 1 and 1/2 cups of frosting. Crumble chopped cookies on top and place second cake layer on top. Evenly cover the second top with about 1 and 1/2 cups of frosting and more chopped cookie crumbles. Top with the third cake layer. Spread the remaining frosting all over the top and sides.
Refrigerate cake for 1-2 hours before slicing.