Preheat oven to 350ºF. Place rack in lower third of oven. Cover two large baking sheets with parchment paper. In a small metal bowl, beat egg whites, adding sugar slowly, until the whites are stiff but not dry. Using a rubber spatula, carefully stir in melted chocolate, vanilla, almond extract and chopped nuts into egg whites. Drop spoonfuls of batter - about 1 1/2 to 2 tablespoons - onto the parchment lined baking sheets. Bake for 12-15 minutes or until tops are completely dry. Do not overbake. Cool completely in pan before removing with a spatula. 12-18 cookies.