A small, buttery nut also called filberts and cobnuts. These wild nuts grow in clusters on the hazelnut tree in temperate zones around the world. The fuzzy outer husk opens as the nut ripens, revealing a hard, smooth shell. They have a bitter brown skin that should be removed before using. Most purchased nuts have the skins removed. If not, heat nuts in a 350° oven 10 to 15 minutes or until the skin begin to flake. Place a small amount of warm nuts in a towel, and rub to remove the skins. Hazelnuts can be purchased unshelled or shelled whole or chopped.