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 Amarene Preserves
1. Preheat oven to 350 F. Line baking sheets with parchment paper or a non-stick baking mat.
2. In a large bowl, beat together butter and sugar until light and fluffy.
3. Beat in egg yolks, vanilla extract and salt. Gradually stir in flour.
4. Form dough into 1-inch diameter balls. Dip in lightly beaten egg whites, then roll in nuts.
5. Place 1 inch apart on prepared cookie sheets. Press down center of each with thumb.
6. Bake for 16 to 18 minutes, or until golden brown. Cool on baking sheet for 5 minutes, then remove to a wire rack to cool completely.
7. Just before serving, fill centers of cookies with Amarene preserves. Or, fill centers with 1/2 teaspoon of preserves before baking.