Old Fashioned Peanut Butter Cake is a good old Southern potluck staple that’s reached cult status. The hot peanutty frosting gets poured right onto the warm cake, and the whole thing gets showered with roasted peanuts. Just divine.
In case you’ve ever wondered, the ratio of attempted recipes to those that actually make it onto the blog is about 1 to 1. That’s to say that for every winner there’s a loser. Today’s lucky winner is an amazing peanut butter cake that has been taunting me from a magazine clipping on my refrigerator door for months. I finally tackled it and now I’m a happy girl.
I can’t imagine there are too many of you out there who wouldn’t enjoy this peanut butter 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.
But can we talk about that frosting?
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.
Another nice thing about this old fashioned peanut butter cake? The batter is thin enough that you can whisk it up in a bowl, no mixer needed.
The older this blog gets, the longer my favorites list gets, but I’m looking you straight in the eye when I say this 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. So good.
Ingredients
- 2 cups all purpose flour
- 2 cups granulated sugar
- 1 tsp baking soda
- 1 tsp salt
- 1 stick (1/2 cup) unsalted butter
- 1 cup water
- 1/2 cup peanut butter (not natural)
- 1/2 cup vegetable oil
- 2 large eggs, room temperature
- 1/2 cup buttermilk, room temperature
- 1 tsp vanilla extract
- 1 stick (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
- roasted peanuts, about 1/2 cup
Instructions
- Preheat oven to 350F
- Spray a 9x13 pan.
- Whisk together the flour, sugar, baking soda, and salt and set aside.
- Heat the butter and water in a small 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.
Make it your own ~
- Make it chunky! Yes, of course, go ahead and use chunky PB for this cake. I would still use smooth for the frosting, but that’s your call.
don’t forget to pin this old fashioned peanut butter cake
112 Comments
Sean Brooks
November 28, 2018 at 7:19 pmReally stoked about this! My girlfriend loves PB cake and so for her birthday I layered this on top of a whole pan of dark chocolate brownies, doubled the icing and used half for filling after mixing in some PB and chocolate chips. Awesome recipe!
Sue
November 28, 2018 at 7:42 pmWhaaaat? Did you save me a piece??
Lisa
November 22, 2018 at 5:03 amThis has become our new family favorite. Peanut Butter Cake (stacked and only peanut butter frosting) was always a staple for birthdays and get togethers…loved by some but not all….this recipe has changed the mind of everyone about peanut butter cake….goes quick, you better get a piece NOW,
Sue
November 22, 2018 at 7:09 amI love that this cake has become a tradition in so many readers’ lives!
gerry
November 21, 2018 at 5:36 pmI never bake but I made this for my sons birthday and my whole family thinks it may be the best cake they ever ate We are die-hard peanut butter fans so perhaps we are biased-but regardless the cake was divine! The frosting is so good-like a peanut butter caramel.
Thanks for a great recipe!
Sue
November 22, 2018 at 4:20 amI’m thrilled that this cake got you baking Gerry! And I love your description of that frosting, makes me want to make this cake right now :)
Babs
November 7, 2018 at 7:01 amOh my gracious! Thank goodness for Google. I was home on a Sunday morning when I remembered a coworkers birthday. He, like my son, is a peanut butter lover. I decided to try my luck at finding a new recipe and stumbled across this one. I had all of the ingredients at home, the reviews looked good so I thought I’d give it a try. This was a HUGE hit. Everyone loved it and made sure I saved this recipe for future events. Hardest part of the entire process was sifting the 3 cups of powdered sugar (probably had something to do with my tendonitis). LOL! Thank you so much for sharing. YUM-O!!
Sue
November 7, 2018 at 7:07 amThank you Babs for coming back to leave this glowing review…you’ve made me hungry for peanut butter cake and it’s only 7 am :)
Diane
November 4, 2018 at 6:32 pmSue, I made your old fashion peanut butter cake for my son’s birthday. Everyone loved it. It was wonderful. I wanted to know if you make a 9 by 13 inch carrot cake? Please send me the recipe. Thanks so very much. Again thanks Diane
Sue
November 4, 2018 at 7:24 pmGosh I don’t Diane, but that should definitely be at the top of my to do list. I’ll probably have to fit it in after the holidays, maybe even closer to spring, but I’ll definitely do it :)
Jaime Greenlaw
November 2, 2018 at 7:33 amMy husband’s favorite cake is a peanut butter cake, for years and years on his birthday I have chosen a random recipe from the internet and not once been happy with what I ended up with. Well my years of searching are over!! This recipe has been printed and added to our family recipe binder!! I can’t say enough how wonderful this cake is. The cake is moist and delicious. The salty peanuts on top are the perfect compliment to the sweetness of the frosting…we will make it again and again!
Sue
November 2, 2018 at 8:46 amI couldn’t be more thrilled!
Rena Pruett
October 30, 2018 at 7:48 amI finally got around to making this cake. What can I say, it was DELICIOUS! I took it to work with me and I will say that it did not last very long. The cake was so moist, not too sweet but just right. It was definitely a hit with the crew!
Sue
October 30, 2018 at 8:25 amThe crew might just demand this on a regular basis! Thanks for coming back to let me know Rena :)
Celine Phang
October 20, 2018 at 6:56 pmI had some chunky peanut butter and yogurt that were about to expire, looked for help to use them up, and ended up here. The result was a moist, soft and utterly delicious cake even though I’m not really a big PB fan. Reduced the sugar by half and omitted the frosting, and am very pleased with the result. In fact, the sweetness was just perfect for me and my family after reducing the sugar.
Thank you!
Kim
October 13, 2018 at 11:23 pmWhy no natural PB? Does it effect the finished cake? Is it OK to use for the icing? Thanks!!
Sue
October 15, 2018 at 6:10 amI only avoid the natural pb because it tends to be more oily than the regular, and is a bit more unreliable in baking, but you can use it if you like.
Layla
October 9, 2018 at 2:03 pmI just tried this recipe! So yummy! Very moist and fluffy. It’s very hard to find buttermilk in Brazil, specially where I live. So I used regular whole milk yogurt instead to make the batter. I did not make the frosting because I like naked cakes better. Thank you for sharing this amazing recipe. It’s now part of my family’s recipe book. Abraços!
Sue
October 9, 2018 at 3:06 pmYou’re so welcome Layla, and I’m glad you enjoyed it even without the frosting!
Diane
September 30, 2018 at 11:51 pmSue, can I make the old fashion peanut butter cake the night before and serve it the next day? Should I refrigerate or leave out?
Thanks Diane
Sue
October 19, 2018 at 10:54 amI would just leave it out, covered with foil, Diane.
Tina
August 27, 2018 at 6:11 pmCan u make a two or three tier cake with this recipe?
Sue
August 27, 2018 at 6:26 pmIt’s a very moist cake, but I think you could make a 2 layer cake.
Clare Lumsden
August 19, 2018 at 12:27 amHands down, this is the BEST bake that I have ever made! Perfect balance of salty sweet crunchy buttery… Recipe is also very forgiving. I am British and got confused about cups/sticks as I prefer metric, and I have even made it quite successfully using almost twice as much butter as I am supposed to. I bake for a small cafe and this bake is always one of the fastest to sell out. Thank you so much Sue!
Sue
August 19, 2018 at 8:02 amA best seller? Wow, that’s amazing. Now you’ve got me craving a piece.
sandra
October 15, 2018 at 12:29 pmcan you use regular milk instead of buttermilk???
Sue
October 15, 2018 at 1:21 pmYes, that should work fine.