Instructions

• Line a 9×9-inch square pan with parchment paper (leave an overhang on two sides if possible for easy removal).
• In a large saucepan, combine 3 cups granulated sugar, 3/4 cup salted butter, and 2/3 cup evaporated milk. Heat over medium, stirring occasionally, until the mixture comes to a boil.
• Continue cooking the boiling mixture, stirring occasionally, until it reaches 233°F on a candy thermometer (about 5 minutes).
• Remove the pan from the heat. Immediately add 2 cups chocolate chips and stir until the chocolate is fully melted and the mixture is smooth.
• Stir in 1 jar marshmallow fluff (7 ounces), 1 cup chopped walnuts, and 1 teaspoon vanilla extract until evenly combined.
• Pour the fudge mixture into the prepared pan and smooth the top with a rubber spatula. If desired, sprinkle extra chopped walnuts on top.
• Refrigerate the pan for about 2 hours, or until the fudge is set.
• Score the top into a 5×5 grid with a knife, then cut along the scored lines and remove the squares to serve.