To it, add the egg mixture spoon by spoon. Split the resulting cream into 2 parts. Color 1 half with a teaspoon of cocoa. Dip the biscotti in milk and arrange them in your preferred pattern.
Smear them with the white cream, then arrange the crumbled meringues and caramelized walnuts on top. Arrange a second layer of biscotti.
Spread the top of the cake with the dark cream.