This is the perfect peanut butter cake recipe. It has the great taste of peanut butter without being overwhelming. I canโt wait to make it again and share it with friends! ~Marci

This old fashioned peanut butter cake is a winner!
Peanut butter cake is a good old Southern potluck staple. It starts with a base of moist peanut butter sheet cake. Then hot peanutty frosting gets poured right over the warm cake, and the whole thing gets showered with roasted peanuts. Just. Divine.
I can’t imagine there are too many of you out there who wouldn’t enjoy this old fashioned sheet cake. I loved everything about it. Starting with the cake itself; peanut butter does something wonderful to the texture. It’s not too sweet, just the way I like it, and very pillowy and moist. And I can’t even with that frosting.
gather your ingredients
- all purpose flour
- granulated sugar
- peanut butter
- I love Jiff for its flavor and texture. Regular creamy pb works best. Natural peanut butter, the kind that separates with an oily layer at the top, doesn’t work as well for baking.
- butter
- eggs
- vegetable oil
- buttermilk
- the buttermilk in the cake and in the frosting gives this cake its Southern charm.
- confectioner’s sugar
- baking soda, salt
- vanilla extract
- crushed peanuts
The hot peanut butter frosting is like peanutty caramel, so good
If you’ve tried my Brown Sugar Peach Cake or my Pumpkin Praline Cake, you might have an inkling about this one. The frosting is cooked in a saucepan, and then literally poured right over the cake. It sets up immediately, almost like fudge or caramel. You have to work quickly, but your reward is that saucepan with a thin layer of peanut frosting clinging to the sides…Let’s just say I stood there scraping it with a spoon for an embarrassingly looooong time.
we love caramel
- Pumpkin Layer Cake with Caramel Frosting
- Caramel Frosted Zucchini Pecan Bars
- Salted Caramel Pot de Crรจme
- Caramel Apple Sheet Cake
- Caramel Apple Bundt Cake
whisk up peanut cake batter right in a saucepan!
The batter is thin enough that you can whisk it up in a saucepan, no mixer or extra bowl needed. That makes this amazing cake dangerously easy to throw together (it could get habit forming.)
the bottom line
The older this site gets, the longer my favorites list gets, but I’m looking you straight in the eye when I say this peanut butter cake is a goodie. You’ll love it, and it will serve you well if you need an easy dessert to bring anywhere this season. The 9×13 cake can serve up to 24 people, right out of the pan. Try it.
“I never bake but I made this for my son’s birthday and my whole family thinks it may be the best cake they ever ate. The frosting is so good, like a peanut butter caramel.
Thanks for a great recipe!!” ~Gerry
Peanut Butter Cake
Video
Equipment
- standard 9×13 baking pan
Ingredients
- 2 cups all purpose flour
- 2 cups granulated sugar
- 1 tsp baking soda
- 1 tsp salt
- 1/2 cup unsalted butter
- 1 cup water
- 1/2 cup creamy peanut butter Note: I used regular peanut butter for this recipe, 'natural'peanut butter does not work as well.
- 1/2 cup vegetable oil
- 2 large eggs, room temperature
- 1/2 cup buttermilk, room temperature
- 1 tsp vanilla extract
frosting
- 1/2 cup unsalted butter
- 1/2 cup creamy peanut butter
- 6 Tbsp buttermilk, you might need a touch more if your frosting is too stiff
- 1 tsp vanilla extract
- 3 cups confectioner’s sugar, sifted
garnish
- 1/2 cup roasted peanuts
Instructions
- Preheat oven to 350F and spray a 9×13 pan with nonstick spray.
- Whisk together the flour, sugar, baking soda, and salt in a medium bowl and set aside.
- Heat the butter and water in a medium/large saucepan until it comes to a boil. Take off the heat and whisk in the peanut butter and oil until smooth. Let cool for a few minutes, then whisk in the eggs, buttermilk, and vanilla until well blended.
- Add the dry ingredients to the wet ingredients, and whisk until just combined.
- Pour the batter into the prepared pan and bake for 40-45 minutes, until the top is golden and a toothpick inserted in the center comes out clean. Set the cake on a cooling rack while you make the frosting.
- To make the frosting, put the butter, peanut butter, and buttermilk in a saucepan and bring to a full boil. Take off the heat and beat in the vanilla and powdered sugar, adding a cup at a time, until the frosting is smooth. I like to put it back on a gentle heat just to rewarm it, stirring constantly, before pouring over the cake. Note: if your frosting is very stiff and not pourable, add a little bit more buttermilk to thin it out.
- Pour the hot frosting over the warm cake, working quickly because the frosting sets up immediately. Spread evenly over cake.
- Garnish with peanuts.
Notes
- Make it chunky!ย Yes, of course, go ahead and use chunky PB for this cake.ย I would still use smooth for the frosting, but that’s your call.
This truly is the favorite in my family, best cake ever!!!
Awwwwww, blushing here ๐
Definitely a great recipe. I left out the peanuts on top, used natural peanut butter for the cake and added peanut butter chips.. oh boy do I love the frosting for sure, best peanut butter frosting ever!!
I could scarf it down with a (big) spoon!
Hi, I need to make a 6โ, 3 layer โsmash cakeโ and they want a peanut butter cake. This cake looks great, but like other Iโve seen says use a sheet pan. Is there a reason not to use layer cake pans?
Thank you
No, you can definitely make this in 2 or 3 layer cake pans, just watch your cooking time…
Should I make extra frosting if I made a 3 layer cake?
I’m not sure, it depends on how you want to arrange it, maybe you’d put a thin layer between the layers, and then drizzle the rest over the top. You can never go wrong making extra frosting, though, then you won’t get caught short. Remember this sets up really fast.
I’m not a big cake fan but his cake is the best I’ve ever eaten! And my son, who doesn’t care for peanut butter too much, loves it, too! I use all brown sugar in place of the sugar. Very easy to make, too! I’m baking one right now for my sisters. Thanks for sharing this recipe!
You’re so welcome Nancy, I’m glad it was a hit!
Hello! How well does this freeze??
I haven’t tried to freeze this cake so I’m not sure, sorry!
Hi Sue, what do you mean by โnot natural โ peanut butter?
I mean that natural peanut butters, the ones that separate and you have to stir them together before using, don’t work as well as a classic homogenized pb like Jiff or Skippy. This is just because of the texture difference.
Hi Sue, Iโm in the UK so am a bit unsure of cup measurements. Do you have the quantities in grammes? This cake looks lovely! Thank you! Paula
Hi Paula …
I lived in the UK for a few years… this is the substitute chart I used for measuring cups to grams:
Flour. 1 cup = 140 grms or 5 oz.
Sugar: 1 cup = 225 grms or 8 oz.
2 Tablespoons = 25 grms or 1 oz.
brown sugar: 1 cup = 170 grms or 6 oz.
Butter: 1 cup = 225 grms or 8 oz.
2 Tablespoons = 25 grms or 1 oz.
I found a larger chart on the internet under โCooking Conversionsโ US to UK!
Never give up!?
Hi. Not sure if anyone’s asked this but can we add a bit more peanut butter ? Just to give it that extra peanut butter punch ? Haven’t tried it yet and wanted some opinions before I do. Thanks !
Hi Latrice…
I lived in the UK for a few years… this is the substitute chart I used for measuring cups to grams:
Flour. 1 cup = 140 grms or 5 oz.
Sugar: 1 cup = 225 grms or 8 oz.
2 Tablespoons = 25 grms or 1 oz.
brown sugar: 1 cup = 170 grms or 6 oz.
Butter: 1 cup = 225 grms or 8 oz.
2 Tablespoons = 25 grms or 1 oz.
I found a larger chart on the internet under โCooking Conversionsโ US to UK!
Never give up!?
DONT KNOW MINE ONLY LASTED 2 HOURS LEFT OUT THEN IT WAS GONE. MAYBE I WILL TRY AND HIDE IT IN THE ICE BOX NEXT TIME
Does it need to be refrigerated
It can sit out on the counter for a couple of days at room temperature, no problem…
Excellent cake. Used a half sheet jelly roll pan for potluck lunch. Cake came out thin and held its shape (donโt want a crumbly cake at a potluck) with a nice thin, crackly frosting. Browned the butter for the cake, dry roasted the garnish peanuts a little more and mixed with 1 TB butter to up the decadence factor (although probably overkill), and sprinkled the frosting before it set with Maldon salt. Definite keeper.
Yum, I bet it was a hit!