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.
I just made brownies last night and made the peanut butter icing what a match made in heaven. The hubby even took some to work for the guys. Love your recipes Christy because they don’t intimidate me and my family loves to eat them. Thank you for sharing!
Thank you so much Angela!! I am so glad to hear that you are enjoying some of the recipes. Food should be simple and easy to make!
Oh, that picture — reminds me so much of my grandmother (Polly) and her sister (Lucille). They were both redheads, and excellent cooks. We lost Polly in 2002 and Lucille last year. I miss them…wish I had some of their recipes, but neither one really wrote anything down. Have you ever had pudding and sauce? That’s an old recipe my grandmother made often when I was a little girl — a not-too-sweet yellow cake baked in a cast-iron skillet with a chocolate sauce poured over it. The sauce was like chocolate gravy with no flour, and the cake looked just like cornbread. In fact, I can remember my dad crumbling it into pinto beans more than once. We’d always let him do it, and everybody would wait for the look on his face when he tasted the sweet cake in his beans! I love your old-time recipes, they really do take me back.
Thanks for the recipe.! It tastes like PB fudge on top of cake!! 🙂 It was crazy how fast it got hard. Will have to be a little faster next time. It was great though!!
Christy, I am so happy to find this recipe, as my Grandmother, use to make it and I haven’t seen it in years. I always wanted the recipe but by the time I was old enough to cook and get her recipes she had passed away at a young 68 years old. I miss her so and your post brough back so many memories of her and my Mother’s sister I called Tissy cause I could not say Aunt Nelda Ann when I was young and heard my Mother call her sister and it came out of my young mouth Tissy. She loved it so that was my own special name for her. She was also a heck of a cook. My Mother, says I have her and my Grandmother’s talent for cooking. I don’t know about that but I know I love to cook and miss it as I am disabled and don’t cook as much as I use to but my husband will try anything if I will just go over it with him. God bless his heart! This is one that we will be trying soon. I also had it as a three layer cake but agree a sheet is much easier!
Also, my daughter fixed the macaroni and cheese out of your cookbook for Christmas and it was delicious. It’s the one on page 95 I think. I love my cookbook and also gave each of my girls one of there own for Christmas! They loved it and I do also.. It was both of their first cookbooks and I can’t think of anything better for their first cookbook! Thanks Christy!! Bring on some more for us!
Please, thank Katyrose for the request. I was just thinking of this frosting the other day.
I am soooooo excited to find this PB frosting! I have been trying to make my Momma’s Pb Cake for yrs. She never would give me a recipe. Why? She was one of those cooks that didn’t need a recipe. A little of this, a dash of that. … 🙂 I do know that all she used was PB, powdered sugar, and water. It was soooo good! I just cannot seem to get the right consistency! So, I am going to be trying this one…SOON! Thanks So Much!
I have been making almost one of your recipe’s a day for about a week or so and I feel so much more confident in my cooking. Even when it doesn’t turn out perfect I still feel confident.
I made this cake and icing with ingredients I had on hand which included some reduced fat items. I think it was great, but next time I will use regular creamy p’nut butter as it didn’t set as well as I had expected. But, the flavor was there and taste was superb.
Making it for just the two of us I had wondered what to do with the extra cake, as we were not going to be able to eat it all. Well the good Lord provided us with some unexpected company and we ended up with 2 pieces leftover for tonight. Tell me fate didn’t step in! LOL
Anyway, thanks again for another moment of sharing with me in my world!
🙂