1. Combine sugar, butter (or margarine) and milk in a 2 1/2 quart saucepan.
2. Bring to a full rolling boil, stirring constantly.
3. Continue boiling 5 minutes over medium/medium-high heat, stirring.
4. Remove from heat, stir in butterscotch chips until melted.
5. Add marshmallow creme and vanilla; beat until blended.
6. Pour into greased 13x9 inch pan.
7. Let cool and serve.