Preheat oven to 350°F. Grease and flour a 9x13 inch pan.

Sift flour and baking powder together and set aside. Cream the butter and 1 cup of the sugar together until fluffy. Add the eggs and 1/2 tsp of the vanilla. Beat well.

Add the flour mixture to the butter mixture, 2 tbsp at a time, mixing well until blended. Pour batter into prepared pan. Bake at 350°F for 30 minutes.

When cake has finished baking, pierce it in 8-10 places with a fork. Let cool completely.

Combine the whole milk, evaporated milk, condensed milk and liqueur and pour over top of cooled cake. Refrigerate for at least two hours before serving

When ready to serve, combine the heavy cream and the remaining teaspoon of vanilla and 1 cup of sugar, whipping until thick. Spread over top of cake. Keep any remaining cake refrigerated. Serve chilled.