Sift the baking powder into the flour before you begin. Set aside until needed. Preheat the oven to 375ºF (190°C). Line the pan with butter before beginning. As an alternative to butter or cooking spray, use parchment paper. Parchment paper is a grease and moisture-resistant paper. When using parchment paper, no butter or cooking sprays are needed because cakes, cookies, or other baked goods won’t stick. It also helps with clean up, since you will have no leftover batter to wash. [3] X Research source If using parchment paper, cut a piece of paper into the shape and size of the bottom of the pan. You can also line the sides of the pan with paper, or you can use cooking spray or butter.

Make sure the eggs are at room temperature when you cook. Take the eggs out of the refrigerator 30 minutes before you begin to make sure they are room temperature. [4] X Research source Do not leave them out of the refrigerator much longer than 30 minutes.

You can also mix the sugar and eggs together with an electric whisk attachment.

Sifting all-purpose flour creates an airy cake, which is what you want to do for a sponge cake. Sift the flour as you measure it when you begin, then sift the flour into the measure before you mix. The baking powder is added when using all-purpose flour because this type of flour has no leavening agent added to the flour, unlike self-rising flour. [6] X Research source

Grease your pan with butter or spray. If you don’t want to use butter or spray, line the pan with parchment paper. Sponge cakes can be time sensitive, so you don’t want to waste any time sifting or preheating the oven.

Try other egg separating methods here: 6 Ways To Separate An Egg. This should be done half an hour before you begin mixing. The eggs are easier to separate when they are cold because both parts seem to hold their shape better. [7] X Research source Leave the eggs out for half an hour so they can warm to room temperature before starting the recipe. Make sure your hands are clean and all soap and oil have been removed. The smallest amount of grease or oil can cause the whites not to stiffen. [8] X Research source Make sure that no egg yolks get into your egg whites, either.

Next, beat in the vanilla extract, water, and lemon zest. Zest is the flavorful outer part of the rind of citrus fruit, such as lemons, oranges, and limes. On a lemon, this is the yellow part; on an orange, this is the orange part of the rind. To zest, use a lemon zester, lemon (or cheese) grater, a vegetable peeler, or a small knife. Make sure to only remove the top layer. If you have removed the white skin, you have gone too deep. [11] X Research source Make sure to beat the yolks in a bowl large enough to add the flour later.

Do not overbeat the eggs. If the egg whites start to divide and separate, or look dull instead of shiny and glossy, they are over beaten. [13] X Research source

To fold, start at the back of the bowl and cut into the batter with a spatula until it hits the bottom of the bowl. Lift the batter over the top of the top ingredient. Then, turn the bowl a quarter of a turn and repeat. Make sure to slide the spatula along the sides. This method will gently mix the ingredients together. [14] X Research source

Do not over mix. This can deflate the cake and make it tough.

To make your butter room temperature, take out of the refrigerator 30 minutes before you begin. Room temperature butter should be soft, but not melted. [18] X Research source

If you do not have an electric hand whisk, you can fold in the flour. Cut the spatula into the mixture, and then lift the batter over the top. Turn the bowl a quarter of a turn and repeat. This method gently mixes in the flour without losing the air.

If you want to add a layer of fruit, jam, or frosting, divide the recipe into two identical pans to make a layered cake.