Heat oven to 350'F. Lightly spray 20 cm square baking pan with vegetable cooking spray. In medium saucepan over low heat, melt corn oil spread. Add sugar; stir until well blended. Remove from heat; stir in cocoa and vanilla. Add egg substitute; stir to blend. Stir in flour and walnuts. Spread batter into prepared pan. Bake 25 minutes or until edges begin to pull away from sides of pan. Cool in pan on wire rack. Sprinkle powdered sugar over top. Cut into squares. Makes 16 brownies. NUTRITIONAL INFORMATION PER BROWNIE: 100 calories; 2 grams protein; 16 grams carbohydrates; 3 grams fat; 0 milligrams cholesterol; 55 milligrams sodium; 5 milligrams calcium.