1/2 cup (125 mL) hot water
2 tbsp (30 mL) instant espresso
1 tbsp (15 mL) granulated sugar
1/2 cup (125 mL) coffee liqueur, such as Kahlúa
6 squares white chocolate, about 6 oz (170 g)
475-g container mascarpone cheese
1/3 cup (75 mL) granulated sugar
1 tbsp (15 mL) vanilla
500-mL container whipping cream, about 2 cups
2 5.3-oz (150-g) pkg giant ladyfinger biscuits
Cocoa powder for dusting or milk-chocolate shavings
In a shallow pie plate or dish, stir water with espresso and 1 tbsp (15 mL) sugar until dissolved. Stir in liqueur and set aside. Coarsely chop chocolate and place in a small microwave-safe bowl. Microwave on medium, stirring halfway through, until almost melted, about 2 min. Stir until completely melted. Let cool slightly.
Place mascarpone in a large bowl. Stir in ⅓ cup (75 mL) sugar and vanilla until smooth. Stir in melted chocolate until combined. In another large bowl, beat cream until soft peaks form when beaters are lifted, about 3 min. Stir a quarter of cream into cheese mixture, then gently fold in remaining cream.
Take half of the biscuits, soak both sides of each in espresso mixture, then place, flat-side down, on the bottom of a 9 × 13-in. (3-L) baking dish. Don’t worry if there are gaps between biscuits. Spoon half of cheese mixture overtop and spread to cover. Soak remaining biscuits in espresso mixture and lay them overtop. Pour any leftover espresso mixture over biscuits, then cover with remaining cheese mixture. Lightly sift cocoa evenly overtop. Cover with plastic wrap and refrigerate at least 6 hours, preferably overnight. Keeps well up to 5 days.