Japaneses sponge Cake

If you like fluffy, and tastey, this is one of the softest cakes that I have ever made. You should hit up the link below. It has all the good stuff there. They really have a great recipe. and easy to follow directions.
https://www.craftsy.com/blog/2016/06/japanese-cake-recipe/
COTTON-SOFT JAPANESE SPONGE CAKE RECIPE
Adapted from Yin Bakes
Makes 1 cake

2/3 cup all-purpose flour
1/4 teaspoon salt
4 tablespoons unsalted butter, melted and slightly cooled
1/3 cup whole milk
5 eggs, separated
1 teaspoon vanilla
1/8 teaspoon cream of tartar
2/3 cup granulated sugar
Note: International readers may enjoy our handy metric conversion guide.

STEP 1:

Position a rack in the middle position of the oven. Preheat the oven to 350 F. Generously grease the bottom and sides of a 9″ springform pan. Line the bottom with a circle of parchment paper and grease the top of that, too.

STEP 2:

In a medium bowl, sift together the flour and salt. Set aside.

STEP 3:

In a separate large bowl, mix the butter and milk until combined. Stir in all five egg yolks and vanilla.