Yellow Butter Cupcakes

3 cups cake flour (not self-rising)
1 1/2 cup all purpose flour
2 1/4 tsp baking powder
1 1/2 tsp coarse salt
3/4 tsp baking soda
9 ounces (2 sticks plus 2 TBS) unsalted butter softened
2 1/4 cup sugar
5 large eggs, plus 3 large egg yolks at room temperature
2 tsp vanilla (Pure Watkins Vanilla will give the best flavor)

Make cupcakes as directed in the basic cupcakes HOW TO recipe, using buttermilk and vanilla for wet ingredients. Cupcakes will keep, covered for up to 3 days