For "very special" occasions, I make Sonja Heine cookies (aka thumbprints). The recipe is one my mom would make for tea party get-togethers.
1 cup butter
1/2 cup brown sugar
2 eggs (separated)
2 cups flour
2 tsp vanilla (other recipes I found online don't have the vanilla)
Jam or jelly
Chopped walnuts (between 1 and 2 cups)
Set aside egg whites, jam and walnuts.
Mix butter, brown sugar, egg yolks, flour, and vanilla.
Make one inch balls and dip in egg whites, then roll in chopped walnuts.
Bake at 350 degrees for 5 minutes.
Remove from oven. Indent center with a teaspoon and fill indentation with jelly. Bake 15 more minutes.
You can halve the batch.