Peanut Butter Fudge Iced Brownies
One bite of these Peanut Butter Fudge Iced Brownies is all it takes to understand why they’ve been a longtime favorite! The old-fashioned boiled peanut butter icing creates a thick, candy-like layer over fudgy brownies for a decadent treat that tastes like it came straight from grandma’s kitchen. Make it once and it’ll be in your regular rotation!

Brownies + Peanut Butter Fudge Icing = A Match Made in Heaven
This icing has been a family staple since I first shared it on Southern Plate back in 2008… and honestly, I’ve lost count of how many of you have made it since!
We’ve always done it over yellow cake, but the day I poured it over brownies, everything changed. A dense, fudgy brownie is the perfect base for this old-fashioned boiled peanut butter icing.
These peanut butter fudge iced brownies perfectly combine rich chocolate with a thick, candy-like peanut butter topping. It’s a combination that feels like it was always meant to be, and once you try it, you’ll wonder why you ever had brownies any other way!
Ingredients
- Boxed brownie mix
- Sugar
- Milk
- Shortening
- Margarine
- Salt
- Vanilla
- Creamy peanut butter
Frequently Asked Questions
I usually get Kroger or some other generic brand – nothin’ fancy here! I’d go for whatever is cheapest where you shop because I’ve never met a brownie mix I didn’t like 😊.
You don’t have to use two boxes of mix, one is fine and you get to taste more of the icing!
To make your brownies thicker, use two boxes of brownie mix. This is how I like to do it! If you do this, you need to cut your oven temperature down to 325°F and add about 15 minutes to the baking process.
Of course! You can use your own recipe or I recommend my friend Susan Spencer’s Grandmothers recipe for Blue Ribbon Brownies. The peanut butter icing will take on the star of the show so go with whatever you prefer and what you have time for, but as for me and my house, we will make them from a mix today.
How to Make Peanut Butter Fudge Iced Brownies
Step 1: Preheat the Oven
Preheat your oven to 350°F and spray a 9×13 or 8×8 inch baking pan.

Tip: If making an 8×8 inch pan of brownies, I’d still use this same amount of icing and just let it be thicker.
Step 2: Mix & Bake Your Brownies
First, you’ll need to whip up some brownies. Just follow the directions on the package. Once they’re baked, let them cool completely before you start on the icing.

Step 3: Make the Icing
Place your milk, sugar, shortening, margarine, and salt in a good sauce pot and put this over medium heat.


Stir constantly while you wait on all of it to melt and come to a boil. Then stop and let it boil on its own (no stirring) for 2 minutes.

Step 4: Beat it, Spread it, & Serve
Remove from heat and stir in your vanilla and peanut butter.


Beat that until it’s nice and smooth, then spread it over your brownies as fast as you can.


Now allow for the icing to cool and set on your brownies. You can occupy yourself during this time by licking the sauce pot clean once it cools enough to let you 😉.
Serve & enjoy!
How to Store Peanut Butter Fudge Iced Brownies
Store your delicious Peanut Butter Fudge Iced Brownies in an airtight container at room temperature for up to 3 days. Alternatively, you can store them in the refrigerator for up to 5 days.

Ingredients
- 1 box brownie mix prepared according to package directions*
- 1-½ cups sugar
- 7 tablespoons milk
- 2 tablespoons shortening
- 2 tablespoons margarine
- ¼ teaspoon salt
- 1 teaspoon vanilla
- ½ cup creamy peanut butter
Instructions
- Prepare brownies according to package directions and allow to cool completely before beginning icing.
For the Icing
- In a heavy saucepot, combine the sugar, milk, shortening, margarine, and salt. Bring to a rolling boil while stirring constantly.
- Once it reaches a rolling boil, stop stirring and let it boil for two minutes or until it reaches the soft ball stage (I don’t use a thermometer, I just let it boil for two minutes).
- Remove from heat and quickly stir in the vanilla and peanut butter. Beat until smooth and quickly spread over the brownies.

This has been one of my favorite recipes for over a decade. My daughter brought them up and I’m disappointed to see that the post is still up but the recipe for peanut butter fudge icing is missing.
WOW! So a couple of things – 1. This stuff tastes amazing!! 2. Definitely heed the directions that this recipes works for both the 9×13 or 8×8 pan. I used a 9×13 pan but doubled the recipe because I didn’t want a thin, skimpy layer of icing. Holy cow. I have twice the amount of icing than I do brownies. I haven’t cut into them yet, but I’m guessing we’re gonna need a huge glass of milk! 3. I didn’t have milk, margarine, or shortening. So I used instant non-fat dry milk made per directions on that package, butter, and coconut oil. It set up quite nice. Thanks for posting this! Easy peasy recipe and I feel like Suzy Home-maker!
LOL, yes it makes a good amount of the icing. So glad to hear the substitutions worked out!!
HELLO I AM CEDRIC PETERSON, I AM TRYING TO FIND ANY ONE THAT’S SELLING REAL BROWNES WITH NUTS AND THE SWEET TASTING PEANUT BUTTER ICING. I AM HOPING THAT YOU CAN HELP ME PURCHASE SOME .
I didn’t pay attention too well to the directions, so I did not let the frosting boil for two minutes AND i poured it on a still warm pan of brownies. It was fine, everyone enjoyed them, and we licked the frosting pot. It is not a hard frosting as far as texture (fudge had me thinking it would be a firm solid coating on top), but it’s in the casserole dish, so it worked out fine.
This frosting sounds so super yummy! ….well like most of your recipes!
Your vanilla bottle reminds me …LOL….I have a big bottle of vanilla my F-in-L brought me from Mexico and my sister saw it in the cabinet and thought I was hiding my alcohol!
LOL, that is too funny!! I am so glad you are enjoying the recipes Margaret!!
A couple of weeks ago I made homemade brownies and wanted to frost them. Soooooo…I started searching and as soon as I saw this, I knew the search was over! 🙂 The peanut butter frosting is to die for. My sons girlfriend ate over half of a 9×11 pan of brownies!! I could just eat the frosting…forget brownies! LOL
I am so glad they were such a hit!!! I could just sit and eat the frosting too Dawn, great minds think alike!!