1. In a heavy cast iron pan, on med-high heat, bring to a boil the sugar, brown sugar and milk, and boil for 5 minutes.
2. Take off the stove, and add the peanut butter, marshmallow fluff, vanilla, butter or.
3. margarine, and walnuts.
4. Stir well, and put into 2 8x8 pans.
5. Let cool, and then with a sharp knife, cut into 2 squares.
6. Store in a plastic container.
7. These can be refrigerated.