Start by lining your 9x13 inch baking pan with parchment paper. This helps with easy removal of the fudge once it has set.
In a heavy-bottomed saucepan, combine the granulated sugar, salted butter, and evaporated milk. Stir over medium heat until the mixture comes to a full rolling boil.
Continue to boil the mixture for exactly 5 minutes without stirring, allowing it to reach the soft-ball stage. If you’re using a thermometer, aim for 234°F (112°C).
Remove the saucepan from heat and immediately stir in the chocolate chips, marshmallow fluff, and vanilla extract. Mix until the chocolate is completely melted and everything is well combined.
Gently fold in the chopped walnuts, ensuring they’re evenly distributed throughout the mixture.
Carefully pour the fudge mixture into your prepared pan, smoothing the top with a spatula. Let it sit at room temperature until set, which can take a few hours.
Once the fudge is firm, lift it out of the pan using the parchment paper. Cut into squares and enjoy your delicious homemade fudge!
