In the pan, turn the heat up to medium-low and heat the butter and milk until butter is melted. Make sure that the milk doesn’t boil.

In a bowl, whisk together the egg yolk, 15g of sugar, and cake flour. Once everything is combined, add in ¼ of the melted butter and melt. Whisk together quickly to make sure the egg doesn’t get cooked from the milk. Once everything is combined, slowly pour in the rest of the milk and butter mixture.

Pour everything back into the pan and turn the heat up to medium. Keep whisking till it turns into a custard texture; it takes around 3-5 minutes. Remove from the heat and add in matcha powder. Once everything is combined, let it rest for 15 minutes.

In a separate bowl, add egg whites and beat with a hand mixer until it comes frothy. Once frothy, add in 15g of sugar and 1 tsp of Vanilla. Keep whisking it together until egg whites become stiff (around 3-4 minutes)

In the baking container, coat the inside with butter and layer on sugar.

Add ¼ of the egg whites into the custard and lightly fold everything together. Once everything is combined, pour the egg custard into the egg white and fold. Don’t overfold to prevent the egg whites from losing their shape.

Pour everything into two separate containers and, using a knife flatten and smooth out the top.

Put it in an air fryer at 330F for 12 Minutes. DO NOT OPEN during the 12 minutes. Every air fryer would be slightly different after 12 minutes; if it hasn’t risen, bake for another 2 minutes. Serve immediately.