Cream the butter, then gradually add the sugar.

Add the egg yolks one at a time, mixing well after each addition.

Beat the egg whites until stiff peaks form, then gently fold them into the batter.

If making a marble cake, separate 1 cup of the batter and mix in the cocoa powder. Grease and flour a cake pan, pour in the batter, then add spoonfuls of the cocoa mixture and swirl with a spatula to create a marbled effect.

Inject or pour 1 1/2 cups of rompope over the cake and cover with a thin layer of Nutella. It's very easy and turns out delicious.

This time I made it marbled. For decoration, I suggest making stripes or piping around the edge. Optionally, you can sprinkle white sprinkles on top. I didn't do this because I didn't have my decorating supplies on hand.