1/2 c. shortening (not butter)
1/2 c. sugar
1 egg yolk
1 1/2 tsp. vanilla extract
1 1/2 c. flour
1/4 tsp. salt
1/2 tsp. baking powder
3 tbsp. milk
1 sq. unsweetened chocolate, melted

Cream shortening and sugar thoroughly. Add egg yolk and vanilla. Sift flour with salt and baking powder. Add to first mixture alternately with milk. Divide dough into two equal parts. To one part add the melted chocolate, mixing well. Roll white dough about 1/8 inch thick on a lightly floured board or lightly floured wax paper. Roll chocolate dough the same size and place on top of white dough. Roll up like a jelly roll and wrap in waxed paper. Chill. When ready to bake, cut in thin slices and place on baking sheet. Bake at 375 degrees for 12 minutes.