PREHEAT oven to 350°F. Grease sides of a 9-inch round cake pan. Line bottom of cake pan with Reynolds Parchment Cooking Paper; set aside.
FOR CAKE, place unsweetened chocolate and butter in a microwave safe bowl. Microwave on HIGH, stirring every 30 seconds, 1 to 1 1/2 minutes, until melted. Cool; set aside. Beat eggs on medium speed with an electric mixer. Beat in sugar, vanilla and salt. Stir in melted chocolate, flour and white morsels. Spread batter in parchment lined pan.
BAKE 35 to 37 minutes. Cool in pan on rack 15 minutes. Loosen sides with a knife; invert cake onto plate. Peel off parchment. Cool. Cake will be dense and fudgy.
FOR GLAZE, place semi-sweet chocolate, water, butter and corn syrup in a microwave safe bowl. Microwave on HIGH, stirring every 30 seconds, 1 to 1 1/2 minutes until melted. Cool. Slide parchment strips under cake edges. Spread glaze over cake. Remove parchment; refrigerate until glaze is set.