In large saucepan over low heat, melt margarine and chocolate, stirring constantly until smooth. Remove from heat and spoon flour into measuring cup; level off. Stir in flour, sugar, nuts, baking powder, salt and eggs; mix well. Cover with plastic wrap and refrigerate at least 1 hour (but up to 24 hours).
Preheat oven to 300F. Shape dough into 1-inch balls; roll each in powdered sugar. Place 2 inches apart on ungreased cookie sheets. Bake for 13-18 minutes or until set. Immediately remove from cookie sheets and cool completely.
Nutrition Info Per Serving (1 cookie): Calories 87.9 Total Fat 3.4 g Saturated Fat 1.6 g Polyunsaturated Fat 0.7 g Monounsaturated Fat 0.9 g Cholesterol 18.1 mg Sodium 57.9 mg Potassium 37.9 mg Total Carbohydrate 14.2 g Dietary Fiber 0.6 g Sugars 9.6 g Protein 1.5 g