Line a 13x9-in. pan with foil; butter the foil with 1 tablespoon butter and set aside. Break German chocolate into 1-in. pieces; place in a bowl. Add the chocolate chips and marshmallow creme; set aside.
In a large saucepan, bring the sugar, milk and remaining butter to a boil over medium heat, stirring often. Reduce heat; simmer, uncovered, 6 minutes, stirring occasionally. Slowly pour over chocolate mixture; stir until mixture is smooth and blended. Stir in nuts.
Pour into prepared pan. Let stand at room temperature until cool. Cut into 1-in. squares. Store in an airtight container in the refrigerator.