Foolproof Chocolate Fudge (Borden's recipe)

3 cups semi-sweet chocolate chips
1 14 oz can sweetened condensed milk
dash of salt
1/2 to 1 cup chopped nuts
1-1/2 tp vanilla extract

In a heavy sauce pan (or double boiler), over low heat, melt chocolate chips with sweetened condensed milk and salt. Stir constantly to avoid scorching on bottom of pan. Remove from heat when chocolate is melted; stir in nuts and vanilla. Spread evenly into wax paper lined 8 inch square pan. Work quickly because this sets up fast. Pat into pan and pat top smooth. Chill for two hours or until firm. Turn fudge onto cutting board, peel off paper and cut into squares. Store leftovers covered in refrigerator.