Peanut Butter Sheet Cake with Peanut Butter Frosting

Peanut Butter Sheet Cake with Peanut Butter Frosting is the kind of dessert that makes everyone’s eyes light up the second it hits the table. And truly, thank you for being here — for loving the classics and trusting me with your baking moments. This is one of those recipes that feels nostalgic, comforting, and completely irresistible.

Right after the first bite of this Peanut Butter Sheet Cake with Peanut Butter Frosting, you’ll understand why it disappears so fast. It’s soft, rich, buttery, and layered with the dreamiest peanut butter frosting that melts slightly into the warm cake. Oh my goodness… it’s incredible.

If you’d like this recipe sent straight to your inbox (along with more crowd-pleasing desserts), be sure to subscribe by email so you never miss a sweet favorite.

This sheet cake is perfect for potlucks, birthdays, family dinners, or any time you need a dessert that feeds a crowd and wins every single time.

Anything but boring!!

Why You’ll Love This Peanut Butter Sheet Cake with Peanut Butter Frosting

This cake is rich but not heavy, sweet but balanced, and incredibly moist thanks to buttermilk and peanut butter.

What Makes This Cake Special?

• Soft, tender crumb
• Deep peanut butter flavor
• Creamy, fluffy frosting
• Feeds a crowd
• Simple pantry ingredients

It’s the kind of cake you’ll make “just once” — and then again next week.

The Taste and Texture

The cake itself is buttery and moist with a gentle peanut butter richness. The frosting is creamy, smooth, and perfectly sweet, spreading like silk over the top.

And when the frosting hits the slightly warm cake? It melts just enough to create the most luscious layer. The smell alone will drive you crazy in the best way.

Ingredients for Peanut Butter Sheet Cake with Peanut Butter Frosting

For the Cake:

• 1/2 teaspoon baking soda
• 1/2 teaspoon salt
• 1 cup unsalted butter, softened
• 1 cup granulated sugar
• 1 cup brown sugar, packed
• 3 large eggs
• 1 cup buttermilk
• 1/2 cup creamy peanut butter
• 1 teaspoon vanilla extract
• 2 cups all-purpose flour
• 1 1/2 teaspoons baking powder

For the Peanut Butter Frosting:

• 1/2 cup unsalted butter, softened
• 1/2 cup creamy peanut butter
• 3 cups powdered sugar
• 3–4 tablespoons milk
• 1 teaspoon vanilla extract

Necessary Tools

• 9×13-inch sheet pan
• Mixing bowls
• Electric mixer
• Whisk
• Spatula

How to Make Peanut Butter Sheet Cake with Peanut Butter Frosting

Let’s walk through it step-by-step.

Step 1: Preheat and Prepare

Preheat oven to 350°F (175°C). Grease and flour a 9×13-inch baking pan.

Step 2: Mix Dry Ingredients

In a bowl, whisk together:

• Flour
• Baking powder
• Baking soda
• Salt

Set aside.

Step 3: Cream Butter and Sugars

In a large bowl, beat together softened butter, granulated sugar, and brown sugar until light and fluffy.

Step 4: Add Eggs and Peanut Butter

Add eggs one at a time, mixing well after each addition.

Mix in peanut butter and vanilla extract until smooth.

Step 5: Alternate Dry Ingredients and Buttermilk

Add dry ingredients in batches, alternating with buttermilk. Begin and end with the dry ingredients.

Mix just until combined — do not overmix.

Step 6: Bake

Pour batter into prepared pan and spread evenly.

Bake for 30–35 minutes, or until a toothpick inserted into the center comes out clean.

Let cool slightly before frosting.

How to Make the Peanut Butter Frosting

In a bowl, beat together:

• Butter
• Peanut butter

Gradually add powdered sugar, mixing until combined.

Add milk one tablespoon at a time until desired spreading consistency is reached.

Stir in vanilla extract.

Spread evenly over cooled (or slightly warm) cake.

What to Serve with Peanut Butter Sheet Cake with Peanut Butter Frosting

This cake pairs beautifully with:

• A glass of cold milk
• Vanilla ice cream
• Chocolate drizzle
• Chopped roasted peanuts on top
• Hot coffee

For a chocolate-peanut butter twist, sprinkle mini chocolate chips over the frosting.

Storage Instructions

Store covered at room temperature for up to 3 days.

Refrigerate for up to 5 days.

To freeze:

• Freeze unfrosted cake tightly wrapped for up to 2 months.
• Thaw and frost before serving.

General Information

Prep Time: 20 minutes Bake Time: 30–35 minutes Total Time: 55 minutes Servings: 12–15 Difficulty: Easy

Perfect for parties and family gatherings.

Nutritional Information (Approximate Per Serving)

• Calories: 520
• Carbohydrates: 60g
• Fat: 28g
• Protein: 8g
• Sugar: 45g
• Saturated Fat: 14g

Values vary depending on ingredients used.

Conclusion

Peanut Butter Sheet Cake with Peanut Butter Frosting is rich, comforting, and completely crowd-pleasing. It’s simple to make, packed with peanut butter flavor, and guaranteed to disappear fast.

If you bake this cake, please leave a review and let me know how it turned out! And if you snap a photo of that perfectly frosted sheet cake, share it on Pinterest — I absolutely love seeing your creations come to life.

Happy baking! 🥜🍰✨