Bake in the oven; baking time depends heavily on size of the pans and how many you are cooking in the oven at a time. I’d estimate 20-25 minutes if using 9 inch rounds, 12-15 minutes for 3 inch rounds, 18-20 for 6 inch rounds. I set a timer for intervals of 10 minutes, rotated the pans after the first 10 minutes and watched the smaller pans carefully. The center of the cake should have a little spongy bounce with light finger pressure, toothpick test should come out just clean, the top will be slightly golden, and the sides may just be pulling away from the cake pan. Cool on a wire rack in the pan for 10 minutes and then remove from the pan to cool on the wire rack completely.