Next, in another bowl, mix together the peanut butter and powdered sugar until smooth. You want a creamy consistency that will easily blend into the chocolate cake later. Once that’s ready, pour half of the chocolate cake batter into your greased 9×13 inch pan, spreading it evenly. Then, take spoonfuls of the peanut butter mixture and dollop it over the chocolate batter. The lumps of peanut butter create that earthquake effect when the cake rises, which is super fun!
After you have your peanut butter blobs in place, carefully pour the rest of the chocolate batter on top. Don’t worry if it doesn’t completely cover the dollops; that’s part of the magic! Before popping it into the oven, sprinkle the chocolate chips and nuts (if using) over the top for an added decadent touch. Bake for about 30-35 minutes, or until a toothpick inserted in the center comes out mostly clean but allows a few gooey bits to stay stuck—it’s chocolate cake, after all!
Once your cake is finished, let it cool in the pan for at least 15 minutes. I love to serve it warm, maybe with a scoop of vanilla ice cream on the side to really elevate the experience. Trust me, this will be a crowd-pleaser!
Pro Tips for Best Results
I tested this three ways: with both creamy and crunchy peanut butter, and I have to say that creamy gives you a wonderfully silky texture while crunchy adds a nice surprise. If you really love peanut butter, you can even mix in some extra peanut butter chips for that double-peanut experience!
Also, make sure to not over-mix your batter once you’ve added the powdered sugar to the peanut butter. I learned this the hard way after one batch turned out a bit too dense. I like to fold the ingredients together gently to ensure that lovely balance of flavors.
Lastly, if you’re planning to serve this cake at a potluck or gathering, prepare for compliments! I always suggest cutting the cake into smaller squares to make it easy for guests to grab and go.
Common Mistakes to Avoid
One common mistake I made on my first attempt was not allowing the cake to cool sufficiently before cutting into it. The layers were still settling, and it ended up being a gooey mess instead of the beautifully layered cake I envisioned. So, be patient—you want to allow it to set for at least 15 minutes! (See the next page below to continue…)