Preheat the oven to 350 degrees F.
Mix the flour and baking powder in a large mixing bowl and let it aside.
Mix the butter and sugar until you have a smooth texture and add the 3 eggs, one by one.
Add the vanilla
Add to the mixture one cup of milk, followed by one cup of flour. Finish with the last cup of flour.
Spread cake batter in an even layer in the pan and sprinkle with rainbow sprinkles.
Bake your cake for 30-35 minutes or until a cake tester comes out clean.
Cut an acetate in long strips of 3 inches high and using a cake ring, stamp out 2 circles (your cake layers) and place them in a new mold with the acetate on the edge.