Sponge Cake Batter

Step 1

Preheat oven to 350°F (175°C). Grease and line a 9-inch round cake pan with parchment paper.

Step 2

In a large bowl, whisk the 4 eggs and 150g sugar together. Place over a pot of simmering water, whisking constantly until the mixture is warm to the touch, about 3 minutes.

Step 3

Remove from heat. Using an electric mixer, beat the egg mixture on high speed until it triples in volume and forms thick ribbons that hold their shape, about 5-7 minutes.

Step 4

Add the 1 tsp vanilla extract and 1/4 tsp salt, and beat for 30 seconds to combine.

Step 5

Sift the 120g flour and 30g cornstarch over the egg mixture. Gently fold with a spatula, cutting through the batter and turning the bowl, until no streaks of flour remain, about 2 minutes.

Step 6

Pour the batter into the prepared pan. Bake until the top is golden and springs back when lightly pressed, about 25-30 minutes.

Step 7

Cool in the pan for 10 minutes, then turn out onto a wire rack to cool completely before serving.