01 -
Combine chocolate chips, sweetened condensed milk, and melted butter in a medium saucepan over low heat, stirring constantly until the mixture is smooth and fully melted.
02 -
Remove the saucepan from heat and stir in vanilla extract and salt until thoroughly blended.
03 -
Line an 20×20 cm baking dish with parchment paper and evenly spread the chocolate fudge mixture into the prepared dish.
04 -
Drop spoonfuls of marshmallow fluff over the surface and use a knife to gently swirl it through the fudge for a marbled effect.
05 -
Transfer the pan to the refrigerator and chill for a minimum of 2 hours or until the fudge is completely firm.
06 -
Once set, lift the fudge out using the parchment paper, cut into squares with a sharp knife, and serve.