INGREDIENTS
1 cup
. butter (, at room temperature)
2 cups
. granulated sugar
2
large eggs
4
egg yolks
1 tbsp
. vanilla extract
4 cups
. all-purpose flour
1 tsp
. baking powder
2 tbsp
. cornstarch
1/2 tsp
. Kosher salt
1 cup
. butter (, at room temperature)
1 tbsp
. vanilla bean paste ((or vanilla extract))
4 cups
powdered sugar
kosher salt
2 tbsp
milk ((enough to make a spreadable consistency))