Preparation Combine milk, brown sugar, butter, and salt in a 3-quart heavy saucepan and bring just to a boil over moderate heat, stirring until sugar is dissolved. Reduce heat to low and simmer, stirring frequently, until mixture registers 238°F on thermometer and a teaspoon of mixture dropped into a small bowl of cold water holds a soft ball when pressed between your fingers (this will take about 30 minutes). Transfer to a heatproof bowl. Beat in vanilla with an electric mixer at medium speed, then add confectioners' sugar a little at a time, beating until fudge is thick and smooth, about 5 minutes. Spread evenly in an ungreased 8-inch square baking pan. Refrigerate, uncovered, until firm enough to cut, about 30 minutes. Cut fudge into 64 squares with a sharp paring knife. Cook's notes:·If desired, stir 3/4 cup walnuts, lightly toasted and chopped, into the fudge before spreading it in the pan. ·The fudge keeps, layered between sheets of wax paper, in an airtight container and refrigerated for up to 5 days.
Preparation Combine milk, brown sugar, butter, and salt in a 3-quart heavy saucepan and bring just to a boil over moderate heat, stirring until sugar is dissolved. Reduce heat to low and simmer, stirring frequently, until mixture registers 238°F on thermometer and a teaspoon of mixture dropped into a small bowl of cold water holds a soft ball when pressed between your fingers (this will take about 30 minutes). Transfer to a heatproof bowl. Beat in vanilla with an electric mixer at medium speed, then add confectioners' sugar a little at a time, beating until fudge is thick and smooth, about 5 minutes. Spread evenly in an ungreased 8-inch square baking pan. Refrigerate, uncovered, until firm enough to cut, about 30 minutes. Cut fudge into 64 squares with a sharp paring knife. Cook's notes:·If desired, stir 3/4 cup walnuts, lightly toasted and chopped, into the fudge before spreading it in the pan. ·The fudge keeps, layered between sheets of wax paper, in an airtight container and refrigerated for up to 5 days.