"Prepared cake" refers to a cake that has been made and is ready to eat or serve. It describes a cake that has been baked, decorated, and is fully made for consumption. Full definition
Pour half of the batter into prepared cake pan. (hungryrabbit.com)
Pour batter into prepared cake pans and bake for 22 - 32 minutes, or until cake tester comes out clean and top springs back to your touch. (amandascookin.com)
Pour batter into prepared cake tin and bake for about 45 minutes or until a tester inserted in the center comes out clean. (easydessert.org)