Line an 8 or 9 inch square baking dish with parchment paper or aluminum foil sprayed with cooking spray.
Place the chocolate chips and sweetened condensed milk into a medium microwave-safe bowl. Heat on high in the microwave in 30-second intervals, stirring in between, until smooth and creamy. It takes me about one minute and 20 seconds in my 1000w microwave.
Pour mixture into the prepared baking pan. Smooth the top of the fudge mixture with a knife, rubber spatula, or offset spatula.
Cover with foil and chill in the fridge for a couple of hours until set.
To cut fudge into clean squares: Before cutting, let the fudge sit at room temp for 5-10 minutes. Remove the slab from the pan and set it on a cutting board. With a sharp knife, cut the fudge into 1 to 1 ½ inch strips, then cut each strip into small squares. Wipe the blade between cuts.
Video
Notes
To keep parchment paper from slipping around the pan, brush some butter into the pan first.
Because there are only two ingredients in this easy chocolate fudge recipe, use high quality chocolate -- you'll be able to taste the difference.
Store in an airtight container at room temperature for 1-2 weeks or in the refrigerator for 2-3 weeks. To freeze fudge, wrap it tightly in wax paper, again in aluminum foil, and place it in a freezer bag. Freeze for a couple of months.