15.25ouncebox brownie mixprepared according to the box instructions
1cupsemi-sweet chocolate chips
Preheat the oven to 350 degrees Fahrenheit and prepare a 9x13 inch baking pan by lining it with parchment paper and lightly spraying the paper with cooking spray.
Place the creamy peanut butter and salted butter in a medium sized microwavable bowl and microwave for 30-45 seconds or until the butter has melted.
Stir the two ingredients together until completely combined.
Pour in the half and half and stir.
Gradually stir in the powdered sugar until completely incorporated. The mixture should end up with a consistency similar to a soft cookie dough.
Once the peanut butter mixture is finished, set the bowl aside while you make the brownie batter.
In a large bowl, prepare the brownie batter according to the box instructions.
Fold in the semi-sweet chocolate chips and stir to combine.
Evenly drop spoonfuls of brownie batter and the peanut butter mixture into the pan, making sure to alternate until you have covered the bottom of the pan.
Use a spoon or knife to gently combine the mixtures together to form a marbled pattern. Do not overmix or you will lose the marbling effect.
Bake in the oven for 35-40 minutes or until the brownie edges are baked and the center has set.
Allow to cool completely, or for about 30 minutes to 1 hour, before cutting and serving.
To Store: Make sure to cover or wrap your Peanut Butter Brownies for maximum freshness and storage. Individually wrapped brownies will last for 1-2 days at room temperature or up to 4 days in the refrigerator.
To Freeze: You can freeze these brownies for 1-2 months and thaw overnight in the refrigerator before serving.
Line the pan with parchment paper for easy removal. Once the brownies have cooled, you can lift the whole batch right out of the pan using the paper.
Use a commercial brand of peanut butter that is fully combined/emulsified. I do not recommend using a “natural” peanut butter because the oil tends to separate.
Make sure your peanut butter is creamy because crunchy peanut butter is difficult to work with.
When swirling the peanut butter into the brownie batter, less is more. If you swirl too much, you will mix the peanut butter into the batter.
These Peanut Butter Brownies are fun to change up if you feel like doing so. Here are some of my favorite ways to change them:
Use Reese’s Peanut Butter Cups or Reese’s Pieces in the brownies instead of the chocolate chips. Chop the cups up roughly before you add them to the brownie mix. You can also sprinkle some on top after the brownies come out of the oven if you would like!
Drizzle the brownies with melted peanut butter or a sprinkle of sea salt when they come out of the oven.