6-Inch Birthday Cake | The Fancy Pants Kitchen

Ingredients

• 1 & 3/4 cups (207g) cake flour
• 3/4 tsp baking powder
• 1/4 tsp baking soda
• 1/4 tsp salt
• 1/2 cup unsalted butter, softened to room temperature
• 1 cup granulated sugar
• 3 large egg whites, at room temperature
• 1/2 cup full-fat sour cream, at room temperature
• 2 tsp pure vanilla extract
• 1/2 cup whole milk, at room temperature
• 1/2 cup rainbow sprinkles
• 1 & 1/2 cups (3 sticks) unsalted butter, softened to room temperature
• 4 ounces cream cheese, softened to room temperature
• 6 cups confectioners’ sugar
• 1/3 cup heavy cream or whole milk
• 1/8 tsp salt