I genuinely crave this. Can’t believe it’s just 3 ingredients!

Line an 8×8-inch baking pan with parchment paper or lightly grease it. Leave a bit of parchment hanging over the sides to make it easier to lift the fudge out later.
In a medium, heavy-bottomed saucepan, combine the chocolate chips, peanut butter, and sweetened condensed milk.
Set the pan over low heat. Stir slowly and steadily with a wooden spoon or heatproof spatula, scraping the bottom and sides often so nothing scorches.
Continue cooking and stirring until the chocolate chips are completely melted and the mixture is smooth, thick, and glossy. This usually takes 5–8 minutes. Do not let it boil.
Once everything is melted and well combined, remove the pan from the heat. Give it a final good stir to be sure the mixture is uniform.
Pour the warm fudge mixture into the prepared pan. Use your spatula to spread it into an even layer, smoothing the top as best you can.
Let the fudge cool at room temperature until it is no longer warm to the touch, then transfer the pan to the refrigerator. Chill for at least 2 hours, or until firm enough to cut cleanly.
Once firm, lift the fudge out of the pan using the parchment paper overhang. Place it on a cutting board and use a sharp knife to cut it into small squares.
Store the fudge in an airtight container, with parchment or wax paper between layers to prevent sticking. Keep it in the refrigerator for firmer fudge, or at cool room temperature if your kitchen isn’t too warm.
Variations & Tips
Because this fudge is so simple, it’s easy to make it your own, just like all those old church-basement cooks used to do. For a little crunch, stir in 1/2 to 1 cup of chopped peanuts, walnuts, or pecans right before spreading the fudge in the pan. If you like a stronger peanut flavor, you can swirl an extra few tablespoons of warmed peanut butter over the top of the fudge and drag a knife through it to make a marbled pattern. For a sweeter, milder chocolate flavor, substitute milk chocolate chips for part or all of the semi-sweet chips; for a darker, less sweet fudge, use dark chocolate chips instead. You can also add a teaspoon of vanilla extract or a small pinch of salt after you remove the pan from the heat to round out the flavors. Around the holidays, a light sprinkle of crushed pretzels, flaky sea salt, or even a few festive sprinkles on top before chilling gives it a special-occasion look with almost no extra effort. If your kitchen runs warm, keep the fudge refrigerated and cut only what you need so the pieces stay nicely firm and tidy on the plate.