Lightly grease 2 9x13 pans, set aside. In a large pan combine butter, sugar and milk, bring to a rolling boil over medium heat stirring constantly. Let boil for another 5 minutes or until candy thermometer reads 234( stir constantly). Remove from heat and add chocolate chips, stir until melted. Add vanilla and marshmallow creme, stir until completely mixed pour into pans and let cool at room temp.