Candice's Shortbread and Jam Thumbprint Cookies

1 c.butter, softened
1/2 c. sugar
2 c. flour
1/2 tsp. vanilla
Your favorite berry jam

Cream butter, sugar, and vanilla. Add flour and mix until well blended. Roll dough into balls (about 1 Tbsp. of dough each). Place balls on an ungreased cookie sheet. Bake at 350 degrees for 12 minutes. Quickly press your finger into each warm cookie to make an indent. Let cool for a few minutes and then roll each cookie in powdered sugar. Allow to cool completely on a wire rack and then roll one more time in powdered sugar. Top each cookie with about a 1/2 tsp. of jam. I love seedless blackberry or raspberry.
Makes 30 cookies.