INGREDIENTS
1 2/3 cups
all purpose flour
1 cup
sugar
1/4 tsp
baking soda
1 tsp
baking powder
3/4 cup
salted butter (170g)
3
egg whites
3 tsp
vanilla extract
1/2 cup
sour cream
1/2 cup
milk
4
large egg whites
1 1/2 cups
sugar
1/3 cup
water
1 pinch
kosher salt
16 oz
unsalted butter, room temperature cut into 1-inch pieces
1 tsp
pure vanilla extract