The BEST Peanut Butter Icing

Made of softened butter, creamy peanut butter, salt, vanilla extract, milk, and powdered sugar, the BEST Peanut Butter Icing recipe combines your favorite staple ingredients for a light and fluffy but rich peanut butter icing that’s perfect for brownies, cupcakes, and cakes!

My mom was clever at taking something simple and making it seem divine! She took an ordinary 9×13-inch pan of brownies, added this peanut butter icing, and made a simple but memorable dessert our whole family loved! With this rich, creamy peanut butter icing on brownies, chocolate cake, and cupcakes are transformed into decadent desserts. They are lip-smacking, addictive, and never last long!

How to Make the BEST Peanut Butter Icing for Brownies

With pantry staples, this peanut butter icing comes together with little effort for a great icing on top of fresh brownies, cakes, and cupcakes!

Ingredients for Fluffy Peanut Butter Icing

• 1/2 cup of butter, softened to room temperature
• 1 cup creamy peanut butter
• 1/4 teaspoon salt
• 1/2 teaspoon vanilla extract
• 2 1/2 Tablespoons milk, whole preferred, plus an optional 1-2 Tablespoons more to thin icing for desired consistency
• 2 1/2 cups powdered sugar

Instructions for the Best Peanut Butter Icing

In a medium mixing bowl with an electric hand mixer, or in a stand mixer beat together the softened butter, peanut butter, salt, vanilla extract, and milk until smooth and creamy.

Then add the powdered sugar and beat well until nice and fluffy, about 1 minute. If needed, add more milk, 1/2 tablespoon at a time, to get the desired consistency.

Spread over completely cooled brownies. Cut and enjoy!

This icing will generously frost a 9×13 pan of brownies, one sheet cake, and modestly ice 24 cupcakes. 

Why do I have to soften butter for Icing? What does softened butter mean?

Softened butter is important for icing because it helps create a smooth and aerated(air-filled, fluffy) texture. So when butter and sugar are creamed together, the butter traps air bubbles. This process is similar to an emulsion; the trapped air expands while baking, resulting in a lighter, fluffier baked good.

Like-wise, room-temperature ingredients bond together more easily, creating a smooth batter or frosting. If the butter is too cold, the ingredients won’t come together correctly, leading to clumpy frosting.

Here’s what to look for in an excellent softened butter. Softened butter should be malleable but not melted or greasy. If you press your finger into it, the impression should hold its shape. You can use a digital thermometer to check the temperature of butter. In a kitchen that’s 70°F, butter that’s been sliced into quarter-inch pieces will be about 60°F after 10 minutes.

More Delicious Desserts

This White Texas Sheet Cake has a subtle almond flavor baked into a buttery, soft white cake that melts in your mouth. This dessert recipe uses simple ingredients for a sweet and classic taste!

I love combining health and dessert! This Red, White, and Blue Fruit Salad is fresh fruit covered in a sweet and tangy sauce that’s so delicious it can be called a dessert, too. While it’s perfect for a refreshing summer side, it would also be a unique and welcomed holiday treat!

Our number-one dessert from the blogs is our Oreo dirt dessert recipes. They are a favorite among all ages and disappear at any party, celebration, or potluck. Our Oreo Dirt Pudding Dessert is a classic rich and creamy dessert with vanilla pudding, cream cheese, and Cool Whip. Our No-Bake Oreo Dessert has a layer of chocolate pudding among all those classic flavors. Both recipes are winners. You won’t be disappointed.