Japanese Cotton Soft Milk Cake

This Japanese cotton soft milk cake is feather-light, delicately sweet, and unbelievably soft with a melt-in-your-mouth crumb.

Ingredients

• 4 large eggs, separated
• 1/2 cup (120 ml) whole milk
• 1/4 cup (60 g) unsalted butter, melted
• 1/2 cup (60 g) cake flour
• 1/2 cup (100 g) granulated sugar, divided
• 1/4 tsp salt
• 1/2 tsp vanilla extract
• 1/2 tsp cream of tartar or 1 tsp lemon juice
• Powdered sugar, for dusting (optional)

Instructions

1. Preheat the oven to 300°F (150°C). Line a 6-inch round cake pan with parchment and lightly grease the sides. Prepare a larger pan for a water bath.
2. In a bowl, whisk the egg yolks, milk, melted butter, vanilla, salt, and half of the sugar until smooth. Sift in the cake flour and whisk just until no lumps remain.
3. In a separate clean bowl, beat the egg whites with cream of tartar until foamy. Gradually add the remaining sugar and whip to soft-medium peaks.
4. Fold one-third of the whipped egg whites into the yolk batter to lighten it, then gently fold in the rest until fully combined and airy.
5. Pour the batter into the prepared pan and tap it lightly once to release large air bubbles. Place the cake pan into the larger pan and add hot water halfway up the sides.
6. Bake for 50-60 minutes, or until the top is lightly golden and the center is set but still jiggly. Turn off the oven, crack the door open, and let the cake rest inside for 10 minutes.
7. Remove from the water bath and cool completely before unmolding. Slice gently and dust with powdered sugar if desired.

Tip: For the signature fluffy texture, fold the meringue in gently and bake low and slow in a water bath to keep the cake moist and cloud-soft.