Snickerdoodle Cake

Using my vanilla cake recipe as the base you can create an absolutely mouthwatering snickerdoodle cake filled with buttery cinnamon swirls and topped with creamy brown sugar cinnamon buttercream frosting. This cinnamon cake goes down in history as one of my best cake masterpieces. Everyone raves about it!
Ingredients
3 and 23 cups 433g cake flour spooned leveled
1 teaspoon salt
2 teaspoons baking powder
34 teaspoon baking soda
1 and 12 cups 340g unsalted butter softened to room temperature

1 and 23 cups 330g granulated sugar
3 large eggs  2 additional egg whites at room temperature
1 Tablespoon pure vanilla extract yes Tbsp!
1 and 12 cups 360ml buttermilk at room temperature
Cinnamon Swirl
12 cup 100g packed light or dark brown sugar
13 cup allpurpose flour 41g or cake flour 38g spooned leveled
1 Tablespoon ground cinnamon
14 cup 4 Tbsp 56g unsalted butter melted
Brown Sugar Cinnamon Buttercream
1 and 14 cups 282g unsalted butter softened to room temperature
8 ounces 226g fullfat brick cream cheese room temperature and sliced into 4 pieces
34 cup 150g packed light or dark brown sugar
1 Tablespoon ground cinnamon
5 and 12 cups 660g confectioners sugar
14 cup 60ml heavy cream or whole milk
1 teaspoon pure vanilla extract
18 teaspoon salt plus more as needed
optional for garnish snickerdoodle cookies
Instructions
Preheat oven to 350F 177C. Grease three 9inch 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.
Make the cake Whisk the cake flour salt baking powder and baking soda together. Set aside.
Using a handheld or stand mixer fitted with a paddle or whisk attachment beat the butter and sugar together on high speed until smooth and creamy about 3 minutes. Scrape down the sides and up the bottom of the bowl with a silicone spatula as needed. Beat in the 3 eggs 2 egg whites and vanilla extract on high speed until combined about 2