Follow these steps to create your own Old-Time Fudge:
1. Line an 8x8x2-inch baking pan or a 9x5x3-inch loaf pan with foil, extending foil over edges of pan. Butter foil; set pan aside.
2. Butter the sides of a heavy 2-quart saucepan. In saucepan combine sugar, milk, chocolate, corn syrup, and salt. Cook and stir over medium-high heat till mixture boils. Clip a candy thermometer to side of pan. Reduce heat to medium-low; continue boiling at a moderate, steady rate, stirring frequently, till thermometer registers 234 degree F., soft-ball stage (20 to 25 minutes).
3. Remove saucepan from heat. Add butter and vanilla, but do not stir. Cool, without stirring, to 110 degree F. (about 55 minutes).
4. Remove thermometer from saucepan. Beat mixture vigorously with a wooden spoon till fudge just begins to thicken. If desired, add nuts. Continue beating till the fudge becomes very thick and just starts to lose its gloss (about 10 minutes total).
5. Immediately spread fudge in the prepared pan. Score into squares while warm. When fudge is firm, use foil to lift it out of pan. Cut fudge into squares. Store tightly covered. Makes about 1-1/4 pounds (32 pieces for a 9x5 or 36 pieces for an 8x8).
Make-Ahead Tip: Up to 2 weeks ahead, prepare fudge. Store as directed.