In a mixing bowl, beat the butter until soft.
Stir in the sugar and egg yolk and cream together until smooth.
Blend in the whiskey and lemon rind.
Add the flour combined with the baking powder and knead until a soft dough is formed.
With lightly floured hands, shape the dough into 2-inch crescents.
Arrange them about 1 1/2 inches apart on a lightly oiled baking tray.
Bake at 350 degree about 15 to 20 minutes.
The cookies should not brown.
While they are still hot, sift confectioner's sugar over and on the sides of the cookies.