Swirled Chocolate and Vanilla Marbled Cake

First, we will grease the mold we are going to use with butter and then we will sprinkle flour on top.

In a bowl we will mix the flour together with the sifted yeast.

In the mixer, we will beat the butter (at room temperature) together with the sugar, until the mixture is whitish and smooth.

Little by little, add 3 egg yolks and a whole egg to the sugar mixture and continue beating. Reserve the remaining egg whites.

Add the sifted flour and milk to this mixture and beat.

In a separate bowl, beat the 3 egg whites together with a pinch of salt, whip until stiff.