Nigella's Irish Cream Tiramisu

Serving :  8  cup

INGREDIENTS 

8 tsp espresso powder dissolved in 250ml / 1 cups water
¾ cup baileys
300 gram savoiardi cookies
2 large eggs
⅓ cup superfine sugar
500 gr mascarpone cheese
2 ½ tsp unsweetened cocoa            

DIRECTION 

1. Mix the coffee with ½ cup of the Baileys in a shallow bowl. Dip the biscuits into this liquid; let them soak on each side enough to become damp but not soggy. Line the bottom of glass dish with a layer of biscuits.
2. Separate the eggs, but keep only one of the whites. Whisk the two yolks and the sugar together until thick and a paler yellow, then fold in the remaining ¼ cup of Baileys, and the mascarpone to make a moussy mixture.
3. Whisk the single egg white until thick and frothy; you can do this by hand with such a little amount. 
4. Fold the egg white into the yolky mascarpone, and then spread half of this mixture on top of the layer of biscuits.
5. Repeat with another layer of soaked Savoiardi, and then top with the remaining mascarpone mixture.
6. Cover the dish with clingfilm and leave in the fridge overnight. 
7. When you are ready to serve, push the unsweetened cocoa through a small tea strainer to dust the top of the tiramisu.

Recipe modified from here