1. Melt butter in medium saucepan over medium heat. Add flour and cook, stirring, 1 minute. Remove from heat and whisk in milk. Return to heat and bring to boil, stirring frequently; boil 1 minute. Remove from heat and stir in egg yolks, one at a time, beating well after each addition. Stir in cocoa, vanilla and salt until smooth.
2. Heat oven to 375 degree F. Butter an 8-cup souffle dish and coat with 1 tablespoon of the granulated sugar; set aside.
3. Beat egg whites at low speed in large mixer bowl until frothy. While gradually increasing speed to high, beat in remaining 2/3 cup granulated sugar 1 tablespoon at a time. Continue beating until glossy and soft peaks form. Stir one quarter of the egg white mixture into chocolate to loosen. Pour chocolate onto remaining egg white mixture and gently fold in. Spoon into prepared souffle dish. With tip of knife, draw a circle on top of souffle 1 inch in from edge.
4. Bake 35 to 37 minutes or until puffed and barely set in center. Sift confectioners' sugar on top. Serve with ice cream and hot fudge sauce, if desired. Makes 8 servings.