3/4 c. + 2 tbsp. butter
1 1/2 c. confectioners' sugar
2 egg yolks
3 tbsp. strong black coffee
Few drops vanilla extract

Make a sugar syrup with the confectioners' sugar and a little warm water, allow it to cool, then add it to the egg yolks. Cream the butter and stir in the sugar/egg mixture. Add the coffee and mix again. Especially good on chocolate cake.