[header] How to make a sponge cake [title] Heat the oven and prepare your pans. [step] Set the oven to 180 ° c , 350 ° f, or gas mark 4. Butter two 9-inch cake pans or 2 12-by-17 inch rimmed baking sheets. 
Line the bottom of your pans with parchment paper, butter the paper, and then sprinkle flour all over it. Gently shake the flour around and shake the excess out of the pan.