Thumb print Cookies

2/3 cup unsalted butter, at room temperature 

1/3 cup granulated sugar 

2 large egg yolks

1 teaspoon vanilla extract 

1/2 teaspoon salt 

1-1/2 cups all-purpose flour 

2 large egg whites

3/4 cup finely chopped nuts of choice 

1/3 cup jam (any flavor)

 Preheat oven to 350 F.  In a large bowl, beat together butter and sugar until light and fluffy. Beat in egg yolks, vanilla extract and salt. Gradually stir in flour. Form dough into 1-inch diameter balls. Dip in lightly beaten egg whites, then roll in nuts. Place 1 inch apart on prepared cookie sheets. Press down center of each with thumb. Bake for 5 minutes, quickly re-indent cookies and continue baking 5 min. fill with jam and bake 3-4 min. or until golden brown. Cool on baking sheet for 5 minutes, then remove to a wire rack to cool completely. 

I made 6 Dozen of these for a friend of mine and about a dozen (nut free ones) for our Family as well. They are like a short bread with jam. Yum!