Peanut Butter Cake

By: Julie Blanner17 Comments
Posted: 1/24/23

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It’s the best blend of sweet and salty… an easy peanut butter cake recipe with a creamy peanut butter frosting on top for a taste of true decadence!

Even better? It’s so easy to make – and it requires no frosting skills at all! Make it in a sheet pan for the easiest indulgence.

This peanut butter sheet cake is a must-have for true peanut butter lovers!

A slice of peanut butter cake on a white plate.

If loving peanut butter is wrong, I don’t want to be right. As you know, my love for peanut butter goes deep. In fact, I’ve got a complete guide to the best Peanut Butter Desserts, and this cake is certainly one of them.

We all know that peanut butter can often create a dry, crumbly mess when it comes to baking. But this cake? No way! It’s light, moist and delicious, and perfect when served with a tall glass of milk.

This peanut butter cake is truly the ultimate. I don’t say that lightly, friends… and I promise I would never steer you wrong. Putting a fresh spin on old-fashioned favorites is what I love about baking!

Even people who think they don’t love peanut butter (side note: what is wrong with them?) will love this easy peanut butter sheet cake. Let’s get started!

Table of Contents

Why You’ll Love this Peanut Butter Cake

Simple Ingredients
Easy to Make
Subtle + Sweet
Wonderful Warm or Cold

This easy peanut butter cake is made primarily of staple ingredients, which makes it easy to whip up any time or day! Is that a good thing or a bad thing? That’s for you to decide.

I pair this cake with a light and fluffy peanut butter frosting. The sweet and salty flavor is amplified by the addition of the frosting, but the peanut butter flavor is not overpowering.

Ingredients and Substitutions

Flour – All purpose flour, no need to sift.
Baking Soda – So the cake rises to perfection.
Salt – This pantry staple brings out all of the flavors of the other ingredients.
White Sugar – Sugar adds the perfect touch of sweetness.
Vanilla – I use vanilla extract in just about everything and it adds just a touch of flavor that makes this cake out of this world good!
Butter – Unsalted. This adds to the tender crumb and moist texture. It can be cold because you’re going to melt it down anyway.
Peanut Butter – Full fat, high quality peanut butter. Just use whatever peanut butter you keep on hand, or learn how to make peanut butter here.
Water – Water is significant in this recipe because it adds moisture to combat any dryness from the peanut butter.
Eggs – The eggs act as a binder, creating more moisture and the perfect spongy texture.

Variations

This cake is topped with decadent peanut butter frosting. If you prefer buttercream, you can find my favorite buttercream frosting recipe right here!
Use crunchy peanut butter in the frosting for added texture. It will still be creamy, but you’ll hit the sweet spot for crunchy peanut butter fans.
Add toppings! Try chocolate chips, chopped up peanut butter cups, a drizzle of chocolate syrup, nuts, or even fresh sliced bananas.

Peanut Butter Frosting Ingredients

Powdered Sugar- This is a must-have ingredient for your frosting because of the incredibly fine texture. No other sugar will do!
Butter- Salted or unsalted, it’s your choice! I always use salted- and again, you’re going to melt it down so don’t worry about temperature in this recipe!
Peanut Butter- I used creamy, full fat peanut butter because I prefer a creamy frosting.
Milk- Because of the thick nature of the peanut butter itself, the milk helps add a little creamy moisture content back into this frosting.

A variety of gold cake pans, loaf pans and muffin baking pan sizes laid out on a marble surface.

Tools to Use

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How to Make

Preheat oven to 400 degrees Fahrenheit. Prepare pan.
First, mix dry ingredients (sugar, baking soda, flour and salt) in a large bowl. Set aside.
Next, combine peanut butter, water and butter in a sauce pan on your cooktop. Bring to a boil.
Gradually add milk, vanilla and eggs.
Mix your melted peanut butter mixture into your dry ingredients in your mixing bowl and pour into a prepared jelly roll pan. Bake until toothpick inserted in the center comes out clean.
As the cake cools, make peanut butter frosting. Combine butter, milk and peanut butter and bring to a boil in a saucepan.
Remove from heat, and gradually add your powdered sugar.
Allow warm cake to cool completely, then frost and serve!

A peanut butter sheet cake, frosted in a sheet pan.

Tips

For the fluffiest cake, don’t over mix your batter.
Don’t Overfill Your Cake Pan – Fill 2/3 full to compensate for rise.
Use the Toothpick Test – Insert a toothpick in the center. When it comes out clean, it’s done.
Yes, you can make this simple old fashioned cake in two round pans for a layer cake! I haven’t tested the timing, so watch carefully while they are in the oven, and don’t fill your layers more than 2/3 full to prevent overflow.

Scaling up, down or substituting? You’ll love this printable Measurement Conversion Chart!

Frequently Asked Questions

What is the secret to super moist cake?

Every recipe is unique, but there are two easy things you must not do if you want a moist cake – don’t overmix, and don’t overbake!

Is peanut butter good for baking?

Peanut butter is great for baking as it’s packed with nutty flavor, and sweet and salty balance. It’s also got plenty of oil! Just don’t substitute natural peanut butter, as your recipes won’t turn out the same.

How to Store

Room Temperature – Store in an airtight container or covered for up to three days.
Refrigerator – Store this cake refrigerated for up to one week.
Freeze – Cake can be stored up to six months in an airtight container without icing. Bring to room temperature to enjoy.

Dietary Considerations

To make this cake Gluten Free, use a 1:1 gluten free flour for baking.
Vegetarian

You’ve got to try this peanut butter cake recipe! Don’t let those dry, crumbly peanut butter cakes of the past keep you from this incredible dessert decadence!

What’s your family’s favorite way to enjoy peanut butter desserts? I’d love to hear from you! If you make this easy peanut butter sheet cake, please come back and share a review with me.