For the cake, butter and flour an 8"x8" cake pan or line it with parchment paper. Preheat oven to 350°F. Mix baking powder and flour together. Add whiskey to milk. With a mixer at medium speed, cream together butter and sugar. Add eggs, one at a time, and beat till fluffy. Alternately, add flour and milk mixture, while blending at low speed, ending with flour. Pour into pan and bake 35-40 min. Cake is done when toothpick inserted in centre comes out clean. Turn out from pan and cool on rack. (Later chill the cake to make it easier to cut.)

For the custard, fill med. saucepan halfway with water and bring to a simmer over med. heat. Place egg yolks and sugar in stainless-steel bowl on top of pot and whisk briskly until mixture thickens and lightens to a fluffy, creamy yellow. Do not let water boil and do not stop whisking or leave the bowl – eggs will curdle. Remove bowl from heat and whisk in Irish Cream liqueur. In a clean bowl with clean beaters, beat egg whites with a pinch of salt until stiff and peaks form. In a separate bowl, beat whipping cream until fluffy and holds peaks. Put room temperature mascarpone in a large mixing bowl with egg yolk mixture and stir to make smooth. Fold egg whites into mascarpone, then fold in whipping cream. Fold gently so you lose as little volume as possible.

To assemble the Tiramisu, trim edges from cake and cut into pieces that will fit into the glasses you’ll be using. For each tiramisu, dip a piece of cake into the coffee mixture and put in bottom of glass. Completely cover cake with layer of custard. Repeat layer of cake and layer of custard. Top with grated dark chocolate and refrigerate until firm. Holds several days in the fridge (but it won’t last that long!).