Foolproof Chocolate Fudge

3 cups (18 ounces) semi-sweet chocolate chips
1 14-ounce can sweetened condensed milk
Dash of salt
1/2 to 1 cup chopped nuts
1 1/2 teaspoon vanilla extract

In heavy saucepan over low heat, melt chocolate chips with condensed milk and salt. Remove from heat; stir in nuts and vanilla. Spread evenly in a wax paper-lined 9-inch square pan. Chill 2 hours or until firm. Turn fudge onto cutting board, peel off paper, and cut into squares. Store leftovers covered in refrigerator.