Piping Cake Batter with a Pastry Bag

It is sometimes convenient to fill a pastry bag with cake batter and then pipe it onto a sheet of parchment paper or into a pan before baking it—for example, when making ladyfingers or cakes with very thin layers. Starting with piped layers is often easier than trying to slice a cake into thin layers with a knife. Virtually any batter, provided it isn’t too runny, can be used in this way.