Preheat oven to 350°F. Grease and lightly flour three 9x2 inch round cake pans. Set aside.
1 cup salted butter, softened
1/2 cup packed light brown sugar
1 and 1/4 cups granulated sugar
Beat the butter on high until creamy. Beat in the granulated and brown sugars. Add eggs and vanilla. Beat on medium speed until everything is completely combined. Set aside.
4 extra large eggs, at room temperature
1 Tablespoon vanilla extract
Combine the flour, baking powder, and salt.
3 cups sifted all-purpose flour
1 Tablespoon baking powder
Slowly add the dry ingredients to the wet ingredients. Beat on low speed for 5 seconds, then add the buttermilk, lemon zest, and lemon juice. Remove from the mixer and stir lightly until everything is just combined.
1 cup buttermilk
zest + juice of 3 medium lemons
Toss the blueberries in 1 Tablespoon of flour and fold into the batter. Batter will be extremely thick. Do not over-mix at any point!
1 and 1/2 cups blueberries
1 Tablespoon all-purpose flour
Spread batter evenly into 3 prepared cake pans. Bake 21-26 minutes or until a toothpick inserted in the center comes out clean. Cool.
Cream Cheese Frosting:
1/2 cup salted butter, softened to room temperature
8 ounces cream cheese, softened to room temperature
3 and 1/2 cups powdered sugar
1 - 2 Tablespoons heavy cream
1 teaspoon vanilla extract
beat cream cheese and butter together on medium speed until no lumps remain. Add powdered sugar, 1 Tablespoon cream, vanilla extract, and salt with the mixer running on low. Increase to high speed and beat for 3 minutes. Add 1 more Tablespoon of cream to thin out, if desired.
Assemble and frost. Refrigerate.