Put all the ingredients into one bowl. The dough will be thick. If it’s too dry, add 1 tablespoon of milk at a time until the dough is pliable but still thick.
Press the dough into the pan with your hands. It doesn’t have to be perfect
Into the oven it goes for about 20 minutes.
Once it cools, the real fun begins. Frosting, sprinkles, maybe even a handwritten “Happy Birthday”