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!
Ingredient Notes:
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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.
Helpful Tip!
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.
FAQs:
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
Ingredients
- 1 1/2 cups granulated sugar
- 1/2 cup brown sugar
- 2 cups flour
- 1 teaspoon baking soda
- 1 teaspoon salt
- 1 1/2 cups milk divided
- 1 cup creamy peanut butter
- 1 cup butter
- 2 teaspoons vanilla
- 2 large eggs
- 1 cup granulated sugar
- 1/3 cup butter
- 1/3 cup milk
- 1/2 cup creamy peanut butter
- 1/2 cup semi-sweet chocolate chips
Instructions
- 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.
Egard83 says
How do we store this? Does it need to be refrigerated?
Karly says
It will last for a couple of days at room temp or in the fridge for 5 or so days. 🙂
Ayla thelen says
This is the best dessert ever!!!!!!!
Karly says
Thanks, Ayla!
Sarah says
I just bought a Half Sheet pan and my pan is 12x17x1 I guess that will be ok???? I really want to use my new pan and this recipe looks amazing.
Karly says
Yes, that should be just fine. Enjoy!
Linda Gray says
Making this again for a potluck at church tomorrow afternoon, hope it turns out as well as the first. Will have to run to the store for peanuts for the frosting. I just buy the snack size, sold at convenience stores and that gives me my about 1/2 cup chopped peanuts for the frosting. Hope this one is as good as the first.
Linda Gray
Linda Gray says
Made the cake for a funeral, and made just like the receipe, and everyone loved it. My only addition was a half a cup of finely chopped salted peanuts I added to the frosting. I liked the texture, and everyone loved the favor and the strong smell of the peanut butter! Also baked my favorite chocolate sheet cake, but everyone preferred the Peanut Butter cake. It was the first dessert gone, not one slice to take home. Will bake and take again, for my next potluck, family dinner or holiday!!! And thank you for the great recipe.
Linda Gray says
looks a little underdone at 15 minutes, and very shiny on top, is this the way? just baked it a couple more minutes, and it is looking more done, also, the baking soda was listed , but couldn’t find anywhere to add it in directions,, so added with salt and flour? did I miss something? will let you know when I get home from funeral tomorrow, if it was well liked.
Karly says
Yes, if it’s not quite finished, go ahead and bake until done. Every oven is different, so it may take a bit longer.
The baking soda gets added with the flour. 🙂
Walter says
Excuse my stupidity. I have never made a cake from scratch. Judging by the ingredient quantity, I don’t see why this cannot be made in a 10″ x 13″ x 3″ pan. Its not worth it for me to buy a half sheet pan just for one recipe. Comments please?
Tricia says
What size did you use for the sheet pan?
Karly says
A half sheet pan is 18×13. 🙂
CakePants says
This looks phenomenal!! But then again, I may be a little biased, since I’m pretty sure 99% of my food cravings are for chocolate peanut butter things. I’ve actually never made a sheet cake, but I’m thinking I should start making up for lost time…
Marsha | Marsha's Baking Addiction says
I LOVE the combination on peanut butter and chocolate – this cake sounds amazing!
Lisa Goodman says
can i use crunchy PB?
Karly says
I haven’t tried it. I think it might make the cake texture a bit strange.