If you are craving a dessert that tastes like it came straight from grandma’s kitchen, old-fashioned peanut butter cake you’ll love is exactly what you need. This classic sheet cake is soft, moist, and packed with rich peanut butter flavor, then topped with a warm, pourable peanut butter icing that melts into the cake as it cools.
This recipe is rooted in traditional home baking. It uses simple pantry staples, comes together quickly, and feeds a crowd with ease. Much like a Texas-style sheet cake, the batter and frosting are both mixed with warm ingredients, creating a tender crumb and a fudgy, irresistible topping.
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Why You’ll Love This Old-Fashioned Peanut Butter Cake
This cake has stood the test of time for good reason.
First, it is incredibly easy to make. You do not need a mixer, fancy tools, or complicated steps. A few bowls and a saucepan are all it takes.
Second, the texture is spot on. The cake is soft and slightly dense, while the warm icing seeps into the top layer, making every bite moist and flavorful.
Third, it is perfect for sharing. Baked in a sheet pan, this cake is ideal for potlucks, family gatherings, holidays, and church suppers.
Finally, it delivers pure comfort. The peanut butter flavor is rich but balanced, sweet without being overwhelming, and deeply nostalgic.
Ingredients for Old-Fashioned Peanut Butter Cake
All quantities are listed in US units.
Cake Ingredients
- 2 cups all-purpose flour
- 2 cups granulated sugar
- 1 teaspoon baking soda
- 1 half teaspoon salt
- 1 cup unsalted butter
- 1 cup creamy peanut butter
- 1 cup water or milk
- 2 large eggs
- 1 teaspoon vanilla extract
Peanut Butter Icing
- 1 half cup unsalted butter
- 1 half cup creamy peanut butter
- 1 third cup milk
- 4 cups powdered sugar
- 1 teaspoon vanilla extract
Ingredient Notes and Substitutions
Peanut butter
Use creamy, shelf-stable peanut butter for best results. Natural peanut butter can separate and affect the texture.
Liquid
Water is traditional and works well, but milk adds a slightly richer flavor to both the cake and icing.
Butter
Unsalted butter allows you to control the salt level. If using salted butter, reduce added salt slightly.
Nut-free option
If needed, sunflower seed butter can be substituted, though the flavor will change.
Step-by-Step Instructions
Step 1: Prepare the Pan and Oven
Preheat your oven to 350°F. Grease a 10 by 15 inch sheet pan or a similar rimmed baking dish.
Step 2: Mix Dry Ingredients
In a large bowl, whisk together the flour, granulated sugar, baking soda, and salt. Set aside.
Step 3: Heat the Peanut Butter Mixture
In a medium saucepan over medium heat, combine the butter, peanut butter, and water or milk. Heat until melted and smooth, stirring frequently. Do not boil.
Step 4: Combine Batter
Pour the hot peanut butter mixture over the dry ingredients. Stir until just combined.
Add the eggs and vanilla extract and mix until the batter is smooth and evenly blended.
Step 5: Bake the Cake
Pour the batter into the prepared pan and spread evenly.
Bake for 20 to 25 minutes, or until a toothpick inserted in the center comes out clean.
Step 6: Make the Icing
While the cake is baking, prepare the icing. In a saucepan, combine the butter, peanut butter, and milk. Heat over medium heat until melted and smooth.
Remove from heat and whisk in the powdered sugar and vanilla extract until the icing is smooth and pourable.
Step 7: Ice the Cake
As soon as the cake comes out of the oven, pour the warm icing evenly over the hot cake. Spread gently if needed.
Allow the cake to cool so the icing can set.
Pro Tips for Success
- Pour the icing over the cake while both are warm for the best texture.
- Do not overmix the batter, as this can make the cake dense.
- Use a whisk for smooth icing with no lumps.
- Let the cake cool slightly before slicing for cleaner pieces.
- Store covered to keep the cake moist for days.
Flavor Variations
Chocolate peanut butter cake
Add 1 cup mini chocolate chips to the batter before baking.
Crunchy topping
Sprinkle chopped peanuts over the icing while it is still warm.
Honey peanut butter cake
Replace 1 quarter cup of sugar with honey for a subtle sweetness.
Vanilla glaze finish
Drizzle a light vanilla glaze over the peanut butter icing for extra sweetness.
Cupcake version
Bake the batter in lined muffin tins and drizzle icing over each cupcake.
Serving Suggestions
Serve this cake slightly warm or at room temperature. It pairs beautifully with a cold glass of milk or a hot cup of coffee.
For gatherings, cut the cake into small squares since it is rich and filling. Add a scoop of vanilla ice cream for a special dessert.
Storage and Freezing Instructions
Storage
Store the cake covered at room temperature for up to 2 days or in the refrigerator for up to 5 days.
Freezing
Freeze individual slices wrapped tightly for up to 2 months. Thaw at room temperature before serving.
Make ahead
This cake actually tastes better the next day as the icing continues to soak into the cake.
Old-Fashioned Peanut Butter Cake You’ll Love
- Total Time: 40 minutes
- Yield: 12 servings
Description
A soft, moist old-fashioned peanut butter sheet cake topped with a warm, pourable peanut butter icing that melts into every bite for a rich, nostalgic dessert everyone loves.
Ingredients
- 2 cups all-purpose flour
- 2 cups granulated sugar
- 1 teaspoon baking soda
- 1/2 teaspoon salt
- 1 cup unsalted butter
- 1 cup creamy peanut butter
- 1 cup water or milk
- 2 large eggs
- 1 teaspoon vanilla extract
- 1/2 cup unsalted butter (icing)
- 1/2 cup creamy peanut butter (icing)
- 1/3 cup milk (icing)
- 4 cups powdered sugar
- 1 teaspoon vanilla extract (icing)
Instructions
- Preheat the oven to 350°F and grease a 10 x 15 inch sheet pan.
- In a large bowl, whisk together flour, sugar, baking soda, and salt.
- In a saucepan, heat butter, peanut butter, and water or milk until melted and smooth.
- Pour the hot mixture over the dry ingredients and stir until combined.
- Add eggs and vanilla and mix until smooth.
- Spread batter evenly in the prepared pan.
- Bake for 20 to 25 minutes until a toothpick comes out clean.
- In a saucepan, heat icing butter, peanut butter, and milk until smooth.
- Remove from heat and whisk in powdered sugar and vanilla until pourable.
- Pour warm icing over the hot cake and spread gently.
- Allow cake to cool before slicing and serving.
Notes
Pour the icing over the cake while both are warm for the best texture. Store covered to keep the cake moist.
- Prep Time: 15 minutes
- Cook Time: 25 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American
Nutrition Facts (Per Serving)
| Nutrient | Amount |
|---|---|
| Calories | ~420 |
| Protein | ~7 g |
| Carbohydrates | ~48 g |
| Fat | ~24 g |
| Fiber | ~2 g |
| Sodium | ~260 mg |
Values are estimates and will vary based on ingredients used.
FAQ About Old-Fashioned Peanut Butter Cake
Why is the icing poured on hot?
Pouring the icing over a hot cake allows it to soak slightly into the surface, creating a moist, fudgy top layer that defines this classic cake.
Can I use crunchy peanut butter?
Creamy peanut butter works best for texture, but crunchy can be used if you enjoy added texture.
Is this cake very sweet?
It is sweet but balanced by the rich peanut butter flavor. Cutting smaller slices helps keep it from feeling too heavy.
Can I make this cake in advance?
Yes, this cake is ideal for making ahead. The flavor and texture improve after resting overnight.
What pan size works best?
A 10 by 15 inch sheet pan is ideal, but a similar-sized rimmed baking dish also works.
Final Thoughts
This old-fashioned peanut butter cake you’ll love is a timeless dessert that brings comfort, nostalgia, and incredible flavor to any table. With its tender crumb, warm peanut butter icing, and simple preparation, it is the kind of recipe that gets passed down and requested again and again. One bite is all it takes to understand why this classic has never gone out of style.