01 -
In a microwave-safe bowl, combine semi-sweet chocolate chips and butter. Melt in 30-second increments, stirring after each, until fully melted.
02 -
Stir in vanilla extract and sweetened condensed milk into the chocolate mixture until well combined.
03 -
Line a square baking dish with parchment paper. Pour in the fudge mixture and smooth out the top evenly.
04 -
Add dollops of Nutella and marshmallow spread on top of the fudge mixture. Use a toothpick, knife, or skewer to gently swirl the toppings into the fudge.
05 -
Place the baking dish in the refrigerator and let the fudge harden for about 3 hours.
06 -
Cut the chilled fudge into squares and enjoy.