Old-Fashioned Peanut Butter Icing

As an Amazon Associate I earn from qualifying purchases.

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!

Hero image for old-fashioned peanut butter icing.

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! And if you don’t love peanut butter check out Boiled Chocolate Icing 

Ingredients for Old-Fashioned Peanut Butter Icing.

Recipe Ingredients

  • Sugar
  • Shortening (I use coconut oil these days)
  • Peanut butter
  • Milk
  • Vanilla extract 
  • Unsalted butter

Helpful Kitchen Tools

How To Make Old-Fashioned Peanut Butter Icing

Add ingredients to a saucepot (except vanilla and PB) and bring to a boil.

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. 

Pouring icing onto cake.

Immediately pour it onto the baked and cooled cake. 

Allow it to cool before serving.

Allow it to cool before serving.

Cutting slices of yellow cake.

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? 

Piece Of Yellow Cake with Old Fashioned Peanut Butter Icing

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. 

Take A Bite! Yellow Cake with Old Fashioned Peanut Butter Icing.

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:

Boiled Chocolate Icing

Italian Cream Cake with Pecan Cream Cheese Icing

7-Minute Frosting (Foolproof Recipe)

Vegan Sweet Potato Cake With Maple Cashew Icing

Creamy Chocolate Frosting

Cappuccino Cake With Cappuccino Buttercream Frosting

Old-Fashioned Peanut Butter Icing

Transform an ordinary yellow cake with this delicious sweet and nutty old-fashioned peanut butter icing recipe.
Prep Time: 20 minutes
Cook Time: 40 minutes
Total Time: 1 hour
Course: Dessert
Cuisine: American
Keyword: cake, icing, peanutbutter
Calories: 318kcal

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

Calories: 318kcal
Tried this recipe?Mention @southernplate or tag #southernplate!

This post was originally published in July of 2008. I updated the photos in August 2019.

Similar Posts

159 Comments

  1. Debbie:
    ~Grins really big~
    You are so kind! Thank you very much for all of your compliments, I’m glad everything looks good and yummy to you!! I just love trying out new recipes, don’t you?
    If you have any questions or requests, just give me a holler!
    (and posh! your blog is FAB!)

  2. Stephanie:
    Thank you! My son went ga-ga over it and my three year old ate nothing but the icing off the cake, then asked for another piece! I hope your son likes it! Thank you for taking the time to read my post!!

  3. What a wonderful story! I got a little teary eyed!And the cake looks out of this world!!!!
    Thanks for you nice comment on my blueberry pancakes.
    As for my photos..I ditched the point and shoot digital camera and my hubby bought me the Canon xti(digital SLR)..it make ALL the difference in the world..and I take all of my photos outside with the natural light. Any cameras built in flash just KILLS the picture. Some of the really good blogs outthere use the Lowel Ego light for the photos. I need to order one..its a table top light that makes the photos look great..Closet Cooking uses that light and all of his photos are fabulous .

  4. I love your blog!! (and thanks for saying kind things about mine, even tho I’m a novice). I’ve always loved Southern Cooking, so I’m very excited to try your recipes. Will try the PB frosting this weekend. And home made biscuits Yum!! And apple butter. I could go on and on… it’s great. I’m getting hungry now. (and it’s late, I really should go to bed)

  5. That was such a beautiful post! I will definitely be making this frosting. Maybe for my little boy’s birthday this Saturday…

  6. Thank you so much for letting me know you tried the biscuits!!!! I’m glad they worked out for you!

    Now I need your PB Buttercream frosting icing recipe if you share it!! I love buttercream!

    Ten thousand “thank you’s” for coming back again and again to my blog!
    We shall be mutual stalkers then! ~muhahaha~
    ~grins~

    1. I love pb icing and this sounds lovely!! My mama loves “fancy” two layers so I’ll try this but ice it by just pouring a bit over each layer!! Ooh some chocolate sheet cake icing poured with it would be tasty also??

  7. Now I have always made Peanut Butter frosting like buttercream to like yours but no cooking. I am going to try to cook it though! It sounds like it might intensify the flavor!! Plus my hubby is a HUGE PB fan anything with Pb he will eat! I think I could slather PB on dog hair and serve it to him!

    Oh and I have looked for a real buttermilk biscuit recipe for a while now. Since I buy buttermilk for my banana breads….and let me say this one was so easy and YUMMY Loved it!
    I am def. going to have to be a blog addict for this one! Thanks for the PB icing recipe! ~Pinky aka Cristal~

    *Ps re-vamping my blog today but I will be adding you onto my stalked blog list so be prepared for some visitors LOL *

Leave a Reply

Your email address will not be published. Required fields are marked *

Recipe or Post Rating