Line 8 x 8 x 2 inch pan with plastic wrap, In a 2-quart sauce pan stir corn syrup and milk to mix, then add chocolate, stirring constantly. Cook over medium-low heat until chocolate is melted. Remove from heat. Stir in vanilla, add sugar. With wooden spoon beat until smooth. Spread in pan. Drop peanut butter by teaspoonfuls onto fudge, and with a knife, swirl peanut butter through fudge to marbleize. Chill 2 hours or until firm. Invert onto cutting board and remove plastic wrap.
Makes about 25-1/2 inch squares.
Cajun Country -- New Iberia, Louisiana