Tiramisu' - cooking recipe

Ingredients

500 g mascarpone (an Italian creamy cheese, you can substitute with ricotta, another Italian cheese, for a low-fat ver)
4 eggs
150 g caster sugar
1/2 - 1 cup strong coffee
300 g ladyfingers or 300 g sponge cakes, cut in squares
cocoa
3 tablespoons brandy (I personally prefer it without spirits) (optional) or 3 tablespoons coffee liqueur (I personally prefer it without spirits) (optional)

Preparation

beat sugar and egg yolks until white and frothy.
whisk egg whites until stiff.
fold mascarpone (or ricotta) into egg mixture.
add egg whites carefully.
pour coffee (and brandy or coffee liqueur if using) in a shallow bowl, dip biscuits (or pieces of sponge cake) in it, taking care not to soak them completely, and put them in a square tin (actually I make it in a glass loaf tin) in a single layer.
cover with the cheese cream and continue layering the ingredients, leaving the cream on top, dust with cocoa.
cover and refrigerate for a few hours or even overnight so that the biscuits have time to become moist and flavourful.