Better Than Sex Cake
["1 box yellow cake mix", "4 sq. semi-sweet chocolate"]
["Prepare cake as directed on box.", "Grate the chocolate into batter; mix gently.", "Grease and flour 10-inch Bundt pan.", "Place 4 cups of batter into pan.", "Bake at 350\u00b0 for 45 to 50 minutes, or until toothpick comes out clean.", "Let cool, then spread with frosting."]
["yellow cake mix", "semi-sweet chocolate"]