Cream one cup confectioner’s sugar with one cup softened butter and a teaspoon vanilla extract. Lightly whip 3 egg whites, room temperature; they just need to be a little frothy, not stiff at all.
Add half the egg whites to the sweet butter along with three tablespoons plain flour. Mix well, blend in the rest of the egg whites with enough flour to make a soft dough.
Pipe dough in 6-inch strips onto a baking sheet lined with lightly oiled parchment paper. Give them room to spread. Bake in a medium (350) oven until edges are browned.
Cool on a rack. For black cat tongues, dip in melted chocolate.
