LOOKING FOR A DESSERT TO FEED A CROWD? THIS YUMMY PEANUT BUTTER SHEET CAKE WILL SERVE PLENTY! PERFECT FOR YOUR NEXT SUMMER BBQ, PICNIC, POT LUCK, OR FELLOWSHIP.
THIS DESSERT….. MMMMM.
The cake turns out moist and delicious and peanut buttery. And the frosting! Rich and even more peanut buttery. 🙂 It forms just a slight crustiness, making it simple to serve. No sticking to the plastic wrap or icing falling down the sides of each piece. I like to serve it on napkins and without silverware for a quick and easy end to a meal!
Certainly, a crowd favorite! Just take it to your next get together and you will find out!
Our S’mores Bars are also a crowd favorite!
By the way, if you are looking for a good sheet pan, I highly recommend the one that I have!
This commercial “half-sheet” by Nordic Ware is made from natural aluminum, which means it won’t rust. (I’ve used mine on a regular basis for years and don’t have even one spot of rust on it!)
I spray it with cooking spray and have never had a problem with anything sticking. So if you want a reliable one that will last, I recommend THIS ONE!

Peanut Butter Sheet Cake
Ingredients
Cake
- 1/2 cup peanut butter
- 1 cup water
- 2 sticks margarine
- 2 cups flour
- 2 cups sugar
- 1 tsp salt
- 1 tsp baking soda
- 2 eggs
- 1/2 cup buttermilk
Frosting
- 1 stick margarine
- 1/2 cup peanut butter
- 6 Tbs buttermilk
- 1 tsp vanilla
- 4 cups powdered sugar
Instructions
- In bowl, mix together flour, sugar, salt and soda.
- In saucepan, mix together peanut butter, water and margarine.
- Bring to a rapid boil and pour over the flour mixture.
- Mix together and add the eggs and buttermilk.
- Pour into greased sheet cake pan. (or 2 - 9x13 pans) Bake at 350° for 20-25 min.
Frosting
- Bring margarine, peanut butter and buttermilk to a rapid boil.
- Remove from heat and add vanilla and powdered sugar.
- Frost cake while the frosting is still hot.
- Let cool completely and cut into bars.
If you’re looking for another dessert to feed a crowd, check out these crazy good S’mores Bars!!!
Can I halve this recipe and make it in a 9×13? I see that it works for two 9×13’s as is but I’m curious if it will actually be enough batter/frosting.
Yes, you can! 🙂
Can you use butter instead of margarine?
Yes, we have made this recipe both ways, with margarine or with butter!
how much is stick margarine? how many grams??
One stick of butter or margarine is about 113 grams. 🙂
Mine was on the gummy side as well. I’ll try sifting the flour next time. I used one 9×13 pan and baked it for 45 minutes. The cake was delicious.
I see the recipe posted with 1/2 milk and using butter. The water on the other recipe is not included. The heat as well is 400 to 350 is the only difference, I LOVE peanut butter my boys as well. Your post I’m just loving so I’m just curious about the buttermilk and the water in the recipe I’m so excited to make for them. Does the Buttermilk give it that added wow to bring out the peanut butter? Any suggestions I’d love you guys are great. Any peanut butter bread maybe? Thanks so very much! God Bless you all
I made this and wouldn’t change a thing! Our family devoured it. This will be a staple at our house
It is at ours, too! 🙂
Not to sound ignorant but I wanted to make this for a family gathering tomorrow, but i don’t bake frequently and the above recipe doesn’t specify all purpose or self rising flour
It’s just all-purpose flour. If we use self-rising in any of our recipes, we will definitely specify. 🙂 Good luck!
I’d like to try your recipe, but I have the same question as the previous person – is the flour used in this recipe all-purpose / plain or self-raising? Many thanks.
Just plain white all-purpose flour 🙂
Do you put the powdered sugar in while the mixture is boiling or take it off the stove. Mine came out thick
As soon as it is all melted and reaches boiling, remove it from the heat and stir the powdered sugar in. Boiling for even a couple of minutes will thicken it right up.
Will this recipe make enough for a round layer cake
Yes it will 🙂
One of our family’s favorite desserts!
Yessss!!