1/2 c. softened butter
1/2 c. firmly packed brown sugar
2 egg yolks
1/2 tsp. vanilla
1 c. sifted flour
1/4 tsp. salt
Jam

Cream butter and sugar. Beat in egg yolks and vanilla. Add flour and salt; mix well. Chill slightly. Preheat oven to 350 degrees. Shape dough into balls about 1 inch in diameter. Place about 1 inch apart on slightly greased cookie sheet. Press thumb into center of cookies and fill with jam. Bake 10-12 minutes until lightly browned. Makes 3 dozen.