1. In a bowl, combine the milk and coffee and stir until the coffee dissolves.
2. If it's difficult for the coffee to dissolve, strain the mixture.
3. Dip the ladyfingers briefly and arrange them on the bottom of a 26cm square baking dish.
For the Cream:
1. Bring 4 cups of the milk to a boil. In a bowl, whisk the eggs well with the sugar. Add the cornflour, cocoa, and coffee. Stir and pour in a little of the hot milk. Stir and strain the mixture back into the hot milk. Stir until the cream thickens.
2. Add the dark chocolate and once it melts, add the butter. Stir until the cream is well thickened and pour it over the ladyfingers. Cover the cream directly with plastic wrap to prevent a skin from forming and let it cool completely.
3. Refrigerate for at least 5-6 hours to chill thoroughly.
For the Topping:
1. Place the whipped cream powder and the milk in the mixer bowl and beat until fluffy.
2. Spread the mixture over the cream layer and sprinkle with the grated chocolate.
3. Refrigerate the dessert for another 1-2 hours to set and serve.
