1 stick butter
1 unbeaten egg
1/4 tsp. baking soda
1 tsp. vanilla
1 c. sugar
2 c. flour
1/4 tsp. cream of tartar
Jam (or whatever for filling)

Mix all ingredients, except jam, and press 1/2 of dough into a greased pan. Cover with jam, then cover with remainder of batter. Bake 375 degrees about 30 minutes or until browned. Cut into squares. Double the recipe - will fill a jelly roll pan.