- 1 pound semisweet chocolate, chopped
- 1 14-ounce can sweetened condensed milk
- 4 tablespoons (1/2 stick) unsalted butter
- 3/4 teaspoon kosher salt
- 1 1/2 cups walnuts or pecans, chopped
- Line an 8-inch square baking pan with a strip of wax or parchment paper, leaving an overhang on two sides.
- In a double boiler or a medium heatproof bowl set over (not in) a saucepan of barely simmering water, heat the chocolate, condensed milk, butter, and salt, stirring occasionally, until smooth. Stir in the walnuts.
- Pour the chocolate mixture into the prepared pan and chill, uncovered, until firm, at least 4 hours and up to 3 days.
- Run a knife around the edges of the pan to loosen the fudge. Using the parchment overhang, lift the fudge out of the pan. Cut into 64 1-inch squares. Serve chilled.
- Storage suggestion: Keep the fudge refrigerated, in an airtight container, for 2 weeks.