This is, hands down, my favorite christmas cookie. I remember when I was little, my grandma (who lived in New York) would send our family (in California) a tin of her cookies, and this cookie was always in it. I can remember rummaging around in the tin looking for one of these little guys. The insides are sandy and crumbly, but, because they are rolled in powdered sugar while still hot, there is a smooth, almost cooling sweetness to the coating on the outside. Made from butter, nuts, sugar and flour, they are pretty simple to make en masse.
Cookie baker's tip: let the hot cookies cool a tiny bit before tossing in the powdered sugar. If they're too hot, they'll fall apart and you'll have to eat the busted ones yourself.