1/2 cup butter at room temperature
1/4 cup sugar
1 large egg separated
1/2 teaspoon vanilla or almond
1 cup flour
1/4 teaspoon salt (optional)
3/4 - 1 cup walnuts toasted and finely chopped (can also use pecans, almonds, or hazelnuts)
1/4 cup raspberry jam (or one of your favorites)
Preheat 350 degrees F (180 degrees C) place the oven rack in the center of the oven.
Line a baking sheet with parchment paper.
In a large bowl beat the butter until smooth, add sugar and beat until well mixed. Add egg yolk, extract and beat until well combined
In another bowl, mix together flour and salt, then add the flour mixture to the batter and beat just until well combined. If the batter is too soft to roll into balls, refrigerate for 30-45 minutes.
In another small bowl, whisk the egg white until frothy. Place chopped nuts on a plate. Roll the batter into 1 inch Then, froll it in egg white and then roll in the nuts. Place on d baking sheet spacing about 2 inches Using your thumb make an indentation into the center of each cookie and then fill the indentation with about 1/2 teaspoon of favorite jam.
Bake 12 minutes, or until cookies are just set and the nuts have nicely browned once done place on wired rack to cool.