Old-Fashioned Peanut Butter Icing
Transform an ordinary yellow cake with this delicious sweet and nutty old-fashioned peanut butter icing recipe. It’s a must-make for peanut butter fans!
Today, I’m sharing a recipe with a big old root system behind it: yellow cake with old-fashioned peanut butter icing. The cake we’re going to use is just a boxed mix because spoiler: it’s not the cake that is important here, it’s the icing. This is my grandmother’s old-fashioned peanut butter icing recipe to be exact and it will forever remind me of my great aunt, Red.
Now, most old-fashioned icing recipes are of the boiled icing variety. If this technique scares you, don’t worry, I’ve included lots of tips for success below to make sure you nail it every time. Trust me, when you get it right and give it a taste, you’ll want to make it again and again. Who can resist a thick layer of sweet yet nutty peanut butter icing on their favorite cake? Certainly not me! The best part of boiled icing is that you pour the hot icing onto the cooled cake and it hardens like fudge… YUM!
To make my peanut butter frosting, you’ll need creamy peanut butter (of course), as well as icing essentials like granulated sugar, vanilla, milk, shortening, and butter. So grab those ingredients and get ready, because I just know you’re going to love this old-fashioned peanut butter icing recipe as much as I do!
Recipe Ingredients
- Sugar
- Shortening (I use coconut oil these days)
- Peanut butter
- Milk
- Vanilla extract
- Unsalted butter
How To Make Old-Fashioned Peanut Butter Icing
In a large saucepot, combine sugar, milk, shortening, margarine, and salt.
Bring to a rolling boil over medium-high heat, stirring constantly to prevent scorching.
Once it reaches a boil, let it boil for two to three minutes without stirring.
Remove from heat and immediately stir in the vanilla and peanut butter.
Beat until icing is smooth and starts to lose its shine.
Immediately pour it onto the baked and cooled cake.
Allow it to cool before serving.
Look at that nice layer of peanut butter fudge icing!
Can you see why yellow cake with old-fashioned peanut butter icing is such a special cake?
This is a sight to behold.
Guess what? It seems like it was a gift from above, but as a precious reminder of my past and its connection to the future, this is my daughter’s favorite cake.
Now excuse me while I dig into this delicious slice of yellow cake!
Storage
Store leftover cake in an airtight container in the fridge for up to 1 week.
Recipe Notes
Here are my tips for success when it comes to boiled peanut butter icing:
-
- The boiling of the icing is the most critical step. Make sure it comes to a rolling boil and then stay right there, timing it. I suggest adding one minute to be on the safe side but don’t go over this as the icing will scorch.
- You absolutely must have your cake done and ready the moment the icing is done.
- Once your icing is finished, remove it from the heat and use a wire whisk to quickly stir in the peanut butter and vanilla until the icing thickens a bit and starts to lose some of its shine. It should still be pourable.
- Don’t try to spread the icing once you’ve poured it. Instead, pour it evenly over the cake so that no spreading is needed.
- Most importantly, unless you lived through the Great Depression, I strongly encourage you not to use this on anything other than a sheet cake. Only those who have the crown of wisdom that comes through age and hardship can ice a layer cake with this.
- If you want more peanut butter flavor, sprinkle the cake with roasted peanuts or crushed nuts.
- Natural peanut butter doesn’t work as well as regular peanut butter in this recipe.
- For creamier icing, you can substitute the milk for buttermilk.
Recipe FAQs
What other cakes work well with old-fashioned peanut butter icing?
You can use any kind of boxed cake mixes, such as vanilla cake, angel food cake, golden cake, white cake, or even chocolate cake (which will suit Reese’s Peanut Butter Cup fans). But if you’re looking for a homemade cake recipe, Aunt Sue’s easy pound cake would be perfect with this peanut butter icing.
Check out these other irresistible icing recipes:
Italian Cream Cake with Pecan Cream Cheese Icing
7-Minute Frosting (Foolproof Recipe)
Vegan Sweet Potato Cake With Maple Cashew Icing
Cappuccino Cake With Cappuccino Buttercream Frosting
Ingredients
- 1 Duncan Hines yellow cake mix made according to package directions and cooled
- 1.5 cups sugar
- 7 tablespoons whole milk
- 2 tablespoons shortening
- 2 tablespoons unsalted butter
- 1/4 teaspoon salt
- 1 teaspoon vanilla extract
- 1/2 cup creamy peanut butter
Instructions
- Prepare cake mix in a 9x13 baking dish as directed on the package. Allow it to cool.1 Duncan Hines yellow cake mix
- In a large saucepot, combine sugar, milk, shortening, butter, and salt. Bring to a rolling boil over medium-high heat, stirring constantly to prevent scorching.1.5 cups sugar, 7 tablespoons whole milk, 2 tablespoons shortening, 2 tablespoons unsalted butter, 1/4 teaspoon salt
- Once it reaches a boil, let it boil for two to three minutes without stirring.
- Remove from heat and immediately stir in vanilla and peanut butter. Beat until icing is smooth and starts to lose its shine. Immediately pour it onto the cake and allow it to cool before serving.1 teaspoon vanilla extract, 1/2 cup creamy peanut butter
Nutrition
This post was originally published in July of 2008. I updated the photos in August 2019.
Christy, I to have precious memories of strong, southern “Godly” women in my life that also were good cooks. This recipe has been passed down from generation to generation in my family. My 25 year old (4th generation) son married in May…guess what he wanted as his grooms cake….” Mawmaw Eva’s peanut butter cake” “my grandmother”. Our baker suggested not to use the icing on the official cake because of decorating purposes. He was insistent upon this cake so we had to come up with a plan. He had his decorated peanut butter grooms cake (boxed and sent home as a favor) but Mawmaw Eva’s cake was served to the guest at the reception. Another memory to be shared with the next generation. Thank you for sharing your memories and allowing me to share mine!!!
I can just taste the peanut butter icing. I don’t know when I first had this but I loved it. My special memory was my first birthday as a wife; we were in seminary at the time. John talked one of our friends into coming over to our tiny apartment to help him make this cake. I think they did a great job and I might have to have one this July. Thank you for the memories!
What a great story…I think all of us ‘southern girls’ whose families were awesome cooks have these memories. I still have my special “Lela”. (and that’s really her name!) She’s my aunt, mom’s sis. My grandmother, mom, and aunt taught me so many things about cooking. Dad too, and I’m forever grateful.
Just subscribed to Southern Plate today, and already loving it, and I’ve decided I have to have your cookbook!
Deb
Christy, This story makes me miss my Grandma and my Aunties and they’ve been gone for years, but a story like this brings them right back. I’m sure all of your departed loved ones are gathered round and cheering you on! It’s nice to see big time success come to someone with such a good heart.
Hugs from me!
And now I’m crying what a heart warming story. The pic. is like looking at my own family members. Thanks for the story and the recipe.
I agree with Brenda. It’s the story behind the recipe that makes it so special!
I just love the way you make your recipes so personal. Reminds me so much of growing up in north Georgia in the 50’s. Thank you for sharing.
About the Peanut Butter Icing,… my sweet Southern Louisiana born and raised,
Mother-in-law, would make this for all of her children, g-children , and all of her great-greats and on…..
Did your Grandmother ever make it with lard, to your knowledge?
Thanks for sharing your story.
Ethyl
Oh, by the way… I have the usual request for my daughter’s birthday cake….
Yep-Peanut Butter Icing ON A YELLOW CAKE!!
Must be that Southern thing:)
Also, my daughter is 43!
Sound familiar?!!!
Ooops,
I meant for this to go to Christy