Japanese Cotton Sponge Cake,

Ingredients

• 4 large eggs, separated

• 60 g (4 tbsp) unsalted butter

• 60 g (4 tbsp) whole milk

• 75 g (½ cup + 1 tbsp) cake flour

• 20 g (2 tbsp) cornstarch

• 70 g (⅓ cup) sugar

• 1 tsp vanilla extract

• ¼ tsp salt

• 1 tsp lemon juice

Instructions

1. Prepare the pan: Line the bottom and sides of a 7-inch (18-cm) round cake pan with parchment paper. Wrap the outside of the pan with foil if using a water bath.

2. Make the milk mixture: Gently heat the butter and milk together until the butter melts. Remove from the heat.

3. Make the batter: Sift the cake flour and cornstarch into the warm butter mixture. Whisk until smooth. Add the egg yolks one at a time, followed by vanilla and salt. Mix until completely smooth.

4. Whip the egg whites: Beat the egg whites with lemon juice until foamy. Gradually add the sugar and continue beating until you have soft-to-medium peaks. Don’t overbeat them until stiff and dry.

5. Combine: Add about one-third of the whipped whites to the yolk batter and gently fold. Add the remaining whites in two batches, folding carefully from the bottom upward. Avoid knocking out the air.

6. Bake: Pour into the prepared pan and gently tap it once or twice to remove large bubbles. Place the pan in a larger baking tray and add about 1–2 cm of hot water.

7. Bake at 150°C (300°F) for about 50–60 minutes, or until the top is golden and the center is set.

8. Turn off the oven and leave the cake inside with the door slightly open for about 10 minutes.

9. Remove from the pan and let it cool. For an especially soft texture, refrigerate it for a few hours before serving.

Tips for a fluffy cake

• Use room-temperature eggs.

• Make sure the mixing bowl for the whites is completely clean and grease-free.

• Fold the whites gently rather than stirring.

• Avoid opening the oven during baking.

• Don’t overbake—the cake should remain moist and tender.