Now, for the magic step that makes this a “dump” cake: I take big dollops of the creamy peanut butter and drop them all over the top of the batter. I use about a teaspoon-sized amount for each dollop, spacing them out. I don’t swirl or spread it. Then, I sprinkle the reserved chopped peanut butter cups (and chopped peanuts, if using) evenly over the entire surface.
I place the dish in the oven and bake for 35-40 minutes. I start checking at 35 minutes. You’re looking for the edges to be fully set and pulling away from the pan, and the center should be set but might still have a slight jiggle—a toothpick won’t come out clean because of all the melty chocolate, and that’s what we want! The top will be cracked, craggy, and smell absolutely incredible. I pull it out and let it cool for at least 20 minutes before serving. It’s dangerously tempting to dive right in, but this rest time lets the molten chocolate and peanut butter settle.
Pro Tips for Best Results
I tested the peanut butter distribution three different ways: swirling it in, mixing it into the batter, and dolloping it on top. Dolloping on top is the clear winner. Swirling mixes it in too much, and it bakes into the cake. Dolloping creates these incredible pockets of warm, soft, almost molten peanut butter right on the surface that are pure heaven in every bite.
Here’s what I learned the hard way about the peanut butter cups: chop them roughly. The first time, I used them whole, and they sank to the bottom and burned. Chopping them into quarters or halves distributes the flavor and ensures they don’t disappear to the bottom. It also gives you more melty bits throughout the entire cake.
For the perfect texture, do not overbake. This cake is meant to be fudgy and dense, not dry and cakey. When you see those cracks on top and the edges are firm, it’s done. The center will firm up as it cools. Overbaking is the only way to ruin this forgiving dessert.(See the next page below to continue…)