1. Preheat oven to 335 degrees.
2. Grinds nuts in food processor.
3. Remove from processor and set aside 1/2 cup to add to batter later and the rest in a bowl for coating the cookie.
4. Add rye flour, AP flour, cardamom, salt, and sugar into the food processor.  Pulse a few times to mix.
5. Add butter, pulse to cut the butter into the flour mixture.
6. Add in 1/2 cup of the ground walnuts.
7. Whisk together vanilla and egg yolk.  Add and pulse in the processor until dough is combined.
8. Roll dough into a log about 1-inch diameter, slice into 1/2 inch pieces and shape into balls.
9. Whisk together egg whites with 1 tablespoon of water.  Dip the top half of the dough ball into the egg whites and then into the ground nuts.  Set nut side up on a baking tray.
10. Press divots into the cookie ball with your thumb.  Place the tray in the fridge for 30 minutes.
11. Bake at 335 for 15 minutes.  Remove from oven, you may need to lightly press into divot again.  Fill with apricot jam.
12. Bake for 10 minutes more.

Best eaten in 2 days.