Tiramisu is much easier to make than you think. Gennaro updates his classic recipe with strawberries and port, but you can use raspberries if you prefer.
Beat the egg yolk and sugar together. Add the mascarpone and mix well to a creamy consistency. Beat the egg white until stiff and fold into the mascarpone mixture to a foamy consistency.
Place the coffee and port in a bowl and dip the biscuits in for a few seconds. Place 2 biscuits in a small glass dessert bowl.
Place a layer of mascarpone cream followed by half of the strawberry, then the other biscuits, some more mascarpone, the rest of the strawberries and finish off with the remainder of the cream.
Place in the fridge for at least one hour. Remove, dust with cocoa powder and enjoy.