In medium saucepan combine sugar, cocoa, cornstarch, and salt; gradually stir in 2 cups milk. Cook over medium heat, stirring constantly, until mixture boils; boil and stir 1 minute. Remove from heat; blend in corn oil spread and 1 teaspoon vanilla. Pour into medium bowl. Press plastic wrap onto surface of pudding and refrigerate until slightly cool. In small mixer bowl combine topping mix, remaining 1/2 cup milk and 1/4 tsp. vanilla; prepare according to topping package directions. Fold 1/2 cup whipped topping into pudding. Blend orange peel into remaining topping. Alternately spoon or pipe chocolate pudding and orange flavored whipped topping into parfait glasses [or use tall champagne glasses to give it a classier look]. Refrigerate until cold. Garnish with orange slices if desired. Gives 7 servings.