2 tbsp. chocolate
1/2 c. milk
2 c. white sugar
1/2 c. Karo
1 tbsp. butter
1 tsp. vanilla

Mix all ingredients except vanilla. Cook, stirring constantly, until mixture boils. Stir occasionally thereafter to see that it doesn't burn until it reaches 238°F (soft-ball stage). Remove from fire and cool. Add vanilla and beat until fudge is thick and surface begins to dull. Pour into pan oiled with butter. Cut into squares.