Fluffy, smooth, and nutty peanut butter icing is the perfect way to finish off cookies, cakes, and brownies. Make your own in just 5 minutes with less than 5 ingredients!
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Knowing how to make peanut butter icing, or really any icing for that matter is the easiest way to level up your home baking game.
It can be thicker, richer, and more flavorful than what you’d buy at the store – and you get to avoid all of the extra ingredients and additives while you’re at it.
It’s incredibly quick to make, uses fewer ingredients than you can count on one hand, and is versatile enough to use as a topping for brownies, chocolate cake… any baked good you can think of!
Peanut butter desserts are the best to make in batches – even those who don’t love dessert can’t seem to resist peanut butter!
Peanut butter balls, fudge, and cookies are guaranteed instant hits.
How to Make Peanut Butter Icing
A full printable version of this recipe with ingredient measurements is available at the bottom of this post.
STEP ONE: Spoon the powdered sugar and peanut butter powder into your stand mixer bowl. Using the whisk attachment, mix until totally combined. (You can make this recipe with a hand mixer or whisk – it’ll just take plenty of muscle!)
STEP TWO: Pour the corn syrup into the bowl. Continue mixing on low speed and gradually add the water.
STEP THREE: Increase the speed to medium and continue whisking until it’s free of lumps and clumps. Keep scraping the sides of the bowl with a rubber spatula to get everything mixed together.
STEP FOUR: Immediately transfer to a piping bag to frost cookies and other sweets. If storing for later, allow it to harden first.
Tips for Preparing This Recipe
- Love chunky peanut butter? Have chopped, toasted peanuts on standby to mix into the final product or sprinkle on top.
- Sift the confectioners sugar before adding to your icing to create that smooth finish
- Corn syrup is optional. However, I think it adds a beautiful, glossy finish.
- Try other flavors! Using half cocoa powder and half peanut butter powder gives you a rich chocolate peanut butter icing (just add a bit more powdered sugar to taste). You can also add peanut butter powder to other favorite icing recipes for some great combinations: caramel and peanut butter, peanut butter cream cheese frosting, etc.
How to Make Peanut Butter Icing the Old Fashioned Way
Old fashioned peanut butter icing takes more work and time but is also relatively easy to make.
- Heat milk (not water) and butter on the stovetop and bring to a boil, stirring continuously.
- After it boils for a couple of minutes, take it off the heat. That’s when you stir in the peanut butter powder and powdered sugar.
- Put it back on the heat and keep stirring until it smooths out.
- Take it back off the heat and pour it right on your cake – while it’s still hot! It’ll harden into the old fashioned peanut butter icing you know and love.
Do You Need to Refrigerate Peanut Butter Icing?
No, it can be kept at room temperature for up to four days.
However, the icing will harden the longer it sits, so I recommend using it right away.
This peanut butter icing recipe yields about 1 cup, so make plenty of cupcakes, cake, or cookies to use up all the icing as quickly as you can.
Quick Fixes for Homemade Peanut Butter Icing
- Too thin? Mix in a tablespoon of powdered sugar at a time until it thickens. If you don’t want it sweeter, then I would recommend a small amount of regular peanut butter if you happen to have it on hand.
- Too thick? Add small amounts of water, milk, half and half, or heavy cream to the icing until it’s thinned enough.
- Too sweet? The trick is to add fat and salt – and salt on its own will have a hard time fully mixing in. Whip some salted butter until it’s airy and fluffy, and then mix it into the icing. A bit of melted butter stirred in can help, too, but might alter the consistency. Finally, try a tiny pinch of salt in a bit of heavy cream.
What is the Difference Between Icing and Frosting?
Icing tends to be richer and coats cakes and cookies well. It has a glossy, almost oily finish. It’s thinner and can make a great glaze!
Frosting, on the other hand, is fluffier and thicker. It’s great for decoration and finishing touches.
If you’re looking for peanut butter frosting, use this recipe instead.
How to Use This Peanut Butter Icing Recipe
- It’s perfect for cookies! Sugar or shortbread cookies are great, but they’ll also pack a great punch on these chocolate kiss cookies
- Slathered onto rich, moist chocolate cupcakes or chocolate cake
- As icing for brownies (especially the chocolate peanut butter icing variation)
- Alongside an extra-sweet banana bread treat
- As an extra ingredient in some s’mores
- Drizzle them on top of some peanut butter rice krispie treats
Other Icing and Frosting Recipes You’ll Love:
- Cool Whip Cream Cheese Frosting
- Peanut Butter Cream Cheese Frosting
- 3 Ingredient Peanut Butter Frosting
- Cream Cheese Frosting Without Butter
Peanut Butter Icing
Ingredients
- 3 cups powdered sugar
- 2 tablespoons peanut butter powder see notes
- 1 teaspoon light corn syrup
- ¼ cup water
Instructions
- Add the powdered sugar and peanut butter powder to the bowl of a stand mixer fitted with the whisk attachment. Mix to combine.
- Next, add the corn syrup, and with the mixer on low speed, slowly drizzle in the water.
- Turn the mixer to medium speed and beat until no lumps remain. Scrape down the sides of the bowl if needed.
- Transfer the icing to a piping bag and use it to frost your favorite cookies. Allow the icing to harden before storing.
Nutrition
This nutrition information is based on the exact products I used in this recipe. Brands and sizes of products could alter exact nutrition and should always be calculated independently.
