Butter 8 or 9 inch square pan; set aside. Combine sugar, cocoa, and salt in heavy 4 quart saucepan; stir in milk. Cook over medium heat, stirring constantly, until mixture comes to full rolling boil. Boil, without stirring, to 234 degrees (soft ball stage) or until syrup, when dropped into very cold water, forms a soft ball that flattens when removed from water. (Bulb of candy thermometer should not rest on bottom of saucepan.) Remove from heat. Add butter and vanilla. Do not stir. Cool at room temperature to 110 degrees. (lukewarm) Beat until fudge thickens and loses some of its gloss. Quickly spread in prepared pan; cool. Cut into 1 to 1 1/2 inch squares.
|