The biggest mistake almost everyone makes when making biscuits (and why it makes you fail)
If you're wondering what went wrong and why your sponge cake isn't light, fluffy, and even, the answer probably lies in a mistake that almost everyone makes unknowingly when mixing the ingredients.
Fatal mistake: mixing too intensively
When you beat eggs and sugar into that lovely, pale, fluffy mixture, you've trapped a lot of air in. This air is essential for the sponge cake to rise and stay fluffy as a cloud while baking.
A common mistake, however, occurs in the next step, when you need to add flour to the fluffy egg mixture.
If you then pick up an electric mixer or use a whisk to wildly stir the flour into the egg mixture, you will do two things:
1. You will displace trapped air: The mass will shrink before entering the oven.
2. You'll activate gluten: Overmixing flour encourages the development of gluten bonds. The result? Instead of a light sponge cake, you'll end up with a rubbery, dense, and hard texture reminiscent of bread.
The golden rule for success: Once you add the dry ingredients, the electric mixer has no more access to the bowl.
How to properly mix flour? Learn the 'folding technique'
To ensure that your sponge cake always turns out perfectly, you need to fold the flour in very gently. Use a silicone spatula and the folding technique:
1. Be sure to sift the flour (preferably directly over the mixture) and add it in two or three parts.
2. Use a spatula to round the edge of the bowl, cut through the center of the mixture, and gently turn it from the bottom up.
3. While doing this, slowly turn the container with your other hand.
4. Stir only long enough for the flour to disappear – a second too long can be too much.
Quick tricks for the perfect sponge cake
Room temperature: Eggs should always be at room temperature before preparation, as this will allow them to capture the most air while whisking.
Proper whisking: Whisk the eggs and sugar until light, thick, and fluffy. When you lift the whisk, the mixture should remain visible on the surface for a few seconds.
Don't overmix: When adding flour, mix it into the mixture gently and for as short a time as possible. It's best to sift it and fold it into the beaten eggs using a spatula and folding technique, as this will keep as much air in the batter as possible.
Do not open the oven: Keep the oven door tightly closed for the first 20 minutes of baking. The sudden drop in temperature causes the air bubbles in the biscuit to collapse.
Viri: King Arthur Baking Company, Serious Eats / J. Kenji López-Alt, The Spruce Eats.
