This peanut butter sheet cake is packed with as much peanut butter as possible for a truly phenomenal taste and texture!
It’s no surprise that we love chocolate and peanut butter around here, so it was high time we created a peanut butter sheet cake!
This cake is so rich and decadent, thanks to the loads of peanut butter in the batter and the rich, fudge frosting poured over the top!
Plus, we love how easy sheet cakes are – minimal fuss, no messing with layers, and you literally just pour the frosting over the top and sooth it out. Could not be easier!
Table of Contents
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Creamy Peanut Butter – You’ll definitely want to use the creamy and not the chunky peanut butter in this recipe. You’ll also want processed peanut butter, like Jif or Skippy – not the natural kind you have to stir together and store in the fridge.
Dry Ingredients – For the dry cake ingredients you’ll need some flour, white and brown sugar, baking soda, and salt.
Wet Ingredients – For the wet cake ingredients we’ll be using butter, eggs, milk, and vanilla extract.
Chocolate Peanut Butter Frosting – You’ll whip this frosting up with some milk, butter, sugar, semi-sweet chocolate chips, and peanut butter! It’s super easy and it makes for perfect crackly frosting.
What Readers are Saying!
“I love cakes and this is so delicious! I gave it a try last night and it is now one of my fave cakes. Thanks so much for sharing.” – Kristen
How to Make Peanut Butter Sheet Cake:
Dry Ingredients: Stir together all of the dry cake ingredients in a bowl or stand mixer with a paddle attachment. Set the bowl aside for now.
Peanut Butter: To get all that peanut butter flavor worked into the cake batter start by adding some butter, a cup of milk, and the creamy peanut butter to a small sauce pan. Bring it to a boil, stirring often.
Combine: Let the peanut butter mix cool for 5 minutes and then pour it into the bowl with the flour and sugar. Next pour in the wet cake ingredients including the vanilla, eggs, and milk.
Mix all that together on low speed until the wet and dry ingredients are just combined. Don’t overmix the peanut butter cake batter!
Bake: When the cake batter is ready you can spread it evenly into a greased, rimmed half sheet pan and then pop it into the oven to bake for 15 minutes. Let the peanut butter sheet cake cool completely before frosting it in the next step.
Frosting: The chocolate peanut butter frosting is super easy and I love that you just pour it right over the top of the cake and wait for it to set! To make it, add the sugar, butter, and milk to a small sauce pan and combine.
Bring it to a boil and boil it for exactly 60 seconds. Remove the pan from the heat and start stirring in the peanut butter and chocolate chips until it all melts and forms into a smooth frosting.
I really love the smooth texture of the chocolate frosting in this recipe, but if you want to switch things up a bit you can mix some chopped peanuts in with the frosting or sprinkle them on top!
Finish: To finish pour the warm chocolate peanut butter frosting over the cooled cake and spread it out evenly with a spatula. Now all you’ve got to do is wait for it to cool and set!
Once the frosting has set it should look sort of shiny or glossy and will have a crackly texture that tastes so good! Go forth and eat all the peanut butter sheet cake, friends.
This cake will last for at least a couple of days at room temperature. You can store it in the fridge for a bit longer, about 5 days in an airtight container or covered with some plastic wrap.
Please use creamy peanut butter for the best results.
A half rimmed sheet pan is 18 x 13.
MORE CHOCOLATE & PEANUT BUTTER RECIPES!
- Chocolate Peanut Butter Cookies
- Chocolate Peanut Butter Lasagna
- Keto Peanut Butter Fudge
- Air Fried Reese’s
- Chocolate Peanut Butter Bundt Cake
- Peanut Butter Stuffed Cookies
Peanut Butter Sheet Cake
- Preheat oven to 400 degrees. Grease a rimmed half sheet pan.
- Add the sugars, flour, baking soda, and salt to the bowl of a stand mixer fitted with the paddle attachment.
- Add 1 cup of milk, peanut butter, and butter to a small sauce pan and bring to a boil, stirring often.
- Remove from heat and let set for 5 minutes to cool. Add to the bowl with the flour and sugar.
- Add the remaining 1/2 cup of milk, vanilla, and eggs to the mixer and turn to low speed. Mix until just combined.
- Spread cake batter into prepared baking sheet and bake for 15 minutes. Cool completely.
- To make the frosting, add the sugar, butter, and milk to a small sauce pan and stir well. Bring to a boil and boil for exactly 60 seconds.
- Remove from the heat and stir in the peanut butter and chocolate chips until smooth and melted.
- Pour warm frosting over the cooled cake and spread with a spatula. Frosting will harden as it cools.
- Cut and serve once frosting has cooled and set.