Peanut Butter Sheet Cake
This Peanut Butter Sheet Cake is a moist sheet cake topped with a gooey peanut butter glaze. Peanut butter lovers, this is your dessert!
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(originally posted 2010)
PEANUT BUTTER SHEET CAKE
My older sister Susan and her husband had a tough time getting pregnant. That’s saying it mildly. They did in vitro fertilization five times! FIVE!
Can you just see the dollar signs when I say that? The fifth time it finally worked. They had a beautiful daughter that they named Jewels. They probably should have named her Mercedes after all that money.
In the early stages of her pregnancy the doctors told her that in order to increase her chances of the embryo implanting successfully she needed to consume a lot of calories.
She did exactly that.
Oh how I was secretly jealous of her free hall pass to eat anything and everything. But the secret, in my opinion, was in the peanut butter. She ate a jar of peanut butter a week…just by the spoonfuls.

EASY BUTTERMILK SUBSTITUTION
For every cup of buttermilk needed, add one tablespoon lemon juice or white vinegar to a liquid measuring cup, and add enough milk until it measures 1 cup. Stir, and let sit for five minutes before using.

The key to this cake is to NOT overbake it! It’s moist unless you cook it too long.

OTHER CAKE RECIPES:
- Chocolate Eclair Cake
- Easy Chocolate Bundt Cake
- Lemon Sheet Cake
- S’mores Cake
- The Best Chocolate Cake
- White Texas Sheet Cake
- Strawberry Cream Puff Cake

Peanut Butter Sheet Cake
Ingredients
Cake:
- 1/4 cup creamy peanut butter
- 1 cup water
- 1/2 cup butter
- 1 cup sugar
- 1 cup brown sugar
- 2 cups flour
- 1 teaspoon salt
- 1 teaspoon baking soda
- 2 eggs
- 1/2 cup buttermilk, see note for easy substitution
- 1 teaspoon vanilla
Frosting:
- 3/4 cup butter
- 6 Tablespoons buttermilk
- 1/2 cup peanut butter
- 3 1/2 cups powdered sugar
- 1 Tablespoon vanilla
Instructions
- Preheat oven to 375 degrees.
For the cake:
- In a medium pot add the peanut butter, water, and butter and bring to a boil. Remove from heat.
- In a separate bowl, mix together the sugar, brown sugar, flour, salt, and baking soda with a fork. Mix together with the peanut butter mixture.
- Add the eggs, buttermilk, and vanilla to the bowl and mix well.
- Stir well and pour into greased or parchment lined cookie sheet pan with a little edge (12X17 jellyroll pan). Bake for 13-15 minutes at 375 degrees. Do not overbake!
For the Frosting:
- In a small pot bring the butter, buttermilk, and peanut butter to a boil. Remove pan from the heat and add the powdered sugar and vanilla. Pour frosting over the warm cake.
Notes



Can I make this in a 13×9 pan? I don’t have a 12×17 jelly roll pan.
Thanks!
Pam
Yes it will just be thicker.
I getting ready to make this and I’m wondering if this would be a good cake to freeze so I can add it to a few meals I’ve made for some people. Thank you for your time. Sharing your recipe.
Yes it freezes great!
Is it all purpose flor ? Or self rising ?
All purpose!
Love this peanut butter recipe. My question is if I double the recipe do l need to double the cooking time?
Are you still baking in jelly roll pans? The time should be the same.
What would make the cake not get done in the middle but the edges are perfect? I have baked the cake twice and it happened both times. Help! The edges and frosting is so delicious but wish I had a whole cake to share.
Well shoot that’s weird. Might be the pan, position in oven? Try cooking a tiny bit longer?
My FAVORITE sheet cake—Love it!!! I make cakes for my family for their birthday and this one gets selected a lot!
I love that!
Love this recipe. I’ve made it several times and it’s always first thing gone at any event.
That is awesome!
Followed directions exactly. The melted butter portion of frosting separated and is an oily mess covering the top of the cake.
Did you whisk it? If you over heat it there could be separation
I can’t wait to try this & if it’s that good, bringing to church functions! I’m assuming the butter in recipe is unsalted but if all I have is salted butter, should I just eliminate the salt in recipe? Thank you 🙂
Yes if using salted eliminate the salt in the recipe
Can this be made into a layer cake? Maybe 2 layers?
I don’t see why not but I haven’t tried it
I’m mildly allergic to peanuts and tend to avoid eating much of anything that contains peanut butter BUT…this was so amazing and I couldn’t stop eating it! No allergic reaction whatsoever thankfully because I’m in LOVE WITH THIS CAKE!!
Oh wow! So glad you didn’t have a reaction!
How far in advance can this be made and how do you need to store it?
I would store it in the fridge if you want it to last longer and up to three days in advance
Made this for our family cookout it was a huge hit ! So yummy !
Thank you!
Absolutely beautiful Taking to a funeral dinner tomorrow
That’s sweet of you
This is my husband’s favorite cake ever..closely tied with the chocolate Texas sheet cake. Sometimes I combine the two and make a chocolate cake with peanut butter frosting or peanut butter cake with chocolate frosting. The recipe here as written is fabulous and win cool points for me with the fam. ♥️
What a great idea!
Yes! I do the same!!
Everything about this is delicious and came together perfectly. The cake reminds me of the cake the Lunch Ladies would prepare for lunchtime at school – my favorite day to eat in the cafeteria when this was on the plate. 🙂 So glad to come across your recipe. I love that this bakes up in 15ms! Perfect for the get-together I was running late for. 🙂 Thank you for sharing!
Thank you!!
I have been looking for a recipes that took me back to my elementary school years in 1961 and when I saw the lunch ladies words. I bookmark this recipe to make. Thank you !!