Combine the hot water and coffee in a shallow plate and allow to cool. Stir in 3 tablespoons of the brandy or almond liqueur when cooled. Dip the sponge fingers into the coffee mixture briefly (so they do not become soggy) then place them in a single layer over the base of a shallow glass serving dish.
Beat the egg whites in a small bowl until the peaks just fold over when the beater is removed. In a separate bowl, beat the mascarpone, egg yolks, icing sugar and 1 tablespoon of the brandy or almond liqueur together until thickened. Fold the egg whites into the mascarpone mixture with 1/2 cup of the grated chocolate. Spread the mixture over the sponge fingers.
Sprinkle the remaining 1/2 cup grated chocolate over the dessert. Cover and chill for several hours, preferably overnight.