1 c. butter
3/4 c. sugar
1 tsp. vanilla
1 egg
3 c. flour
1 tsp. cream of tartar
1 tsp. baking soda

Blend first 4 ingredients together. Add gradually the remaining ingredients. Chill dough in ball for 1 hour or so. Roll thin. Cut out small circle. Place on cookie sheet. Fill with jam. Place another circle on top. Bake at 375 degrees approximately 10 minutes.

Note: I cut a hole in top circle with a thimble so jam will show through. Can add a little more jam after baking.