Question: how much cake batter do i need for a 9x13 pan?
Answer: A 13-by-9-inch pan holds 12 cups. And a standard cupcake pan, with 1/2 cup batter in each of six cups, holds 3 cups. So a two-layer cake batter should convert easily to 12 cupcakes or a sheet cake. The trick after that is figuring out how to adjust the baking time.