Tasty Tuesday - Jam Jam's

This weeks TT are Jam Jam's, I first made these when my dad was visiting at his request. I believe that all the cookies were eaten up within 48hours.

Prep Time: 40 minutes
Cooking Time: 10 minutes
Cooling Time: 10 minutes

Ingredients:
3/4 cup butter, softened
1/2 cup white sugar
2 egg yolks
1 1/4 cups all-purpose flour
1/2 cup whole wheat pastry flour
1/2 tsp vanilla
1/2 cup strawberry jam

Directions:
1. Preheat the oven to 375 degrees F (190 degrees C).
2. In a medium bowl, cream together the butter, white sugar, vanilla and egg yolks. Mix in flour a little bit at a time until a soft dough forms. Roll dough into 1 inch balls. If dough is too soft, refrigerate for 15 to 20 minutes. Place balls 2 inches apart onto ungreased cookie sheets. Use your finger or an instrument of similar size to make a well in the center of each cookie. Fill the hole with 1/2 teaspoon of preserves.
3. Bake for 8 to 10 minutes in the preheated oven, until golden brown on the bottom. Remove from cookie sheets to cool on wire racks.