Biscuit Layered Cake

Whisk together eggs and confectioner's sugar in a heatproof bowl set over simmering water until the mixture reaches 160°F (71°C) and becomes pale and thick, about 5-7 minutes. Remove from heat and let cool slightly.

Soften the butter at room temperature and fold it gently into the cooled egg mixture until fully incorporated and creamy.

Combine rum with 1/4 cup water in a shallow dish. Quickly dip each biscuit into the rum mixture for 1-2 seconds per side until lightly moistened but not saturated.

Arrange half of the dipped biscuits in a single layer at the bottom of a rectangular dish.

Spread half of the egg-butter cream mixture over the biscuit layer.

Layer the remaining dipped biscuits over the cream.

Top with the remaining egg-butter cream, spreading it evenly to the edges.

Fold the whipped cream gently into any remaining cream mixture or spread directly over the top layer if preferred.

Sift the grated chocolate evenly over the entire surface as the final garnish.

Cover with plastic wrap and refrigerate for at least 4 hours or overnight to allow flavors to meld and the cake to set before serving.