If you are looking for a dessert that feels nostalgic, comforting, and wonderfully simple, this easy old-fashioned peanut butter cake recipe is exactly what you need. This classic cake has been passed down through generations because it is reliable, rich in flavor, and made with pantry staples most home cooks already have on hand. Soft, tender cake meets a warm peanut butter frosting that melts right into the top, creating a dessert that tastes like it came straight from a family potluck table.
This is not a fancy layered cake or a modern bakery-style dessert. It is a humble sheet cake that delivers big flavor with minimal effort, making it perfect for everyday baking, holidays, or feeding a crowd.
Why You’ll Love This Easy Old-Fashioned Peanut Butter Cake
There are so many reasons this recipe has stood the test of time.
- It uses simple ingredients with no complicated steps
- The cake stays moist and tender for days
- The peanut butter flavor is rich but not overwhelming
- The warm frosting spreads easily and sets beautifully
- It is perfect for potlucks, family dinners, and bake sales
If you love classic desserts that focus on flavor rather than fuss, this cake belongs in your recipe box.
Ingredients for Easy Old-Fashioned Peanut Butter Cake
Cake Ingredients
- 2 cups all-purpose flour
- 2 cups granulated sugar
- 1 teaspoon baking soda
- 1/2 teaspoon salt
- 1 cup water
- 1/2 cup unsalted butter
- 1/2 cup creamy peanut butter
- 2 large eggs
- 1 teaspoon vanilla extract
Peanut Butter Frosting Ingredients
- 1/2 cup unsalted butter
- 1/2 cup creamy peanut butter
- 1/3 cup milk
- 4 cups powdered sugar
- 1 teaspoon vanilla extract
Ingredient Notes and Substitutions
Peanut Butter
Use regular creamy peanut butter for the best texture. Natural peanut butter tends to separate and can make the cake greasy or uneven.
Butter
Unsalted butter allows you to control the salt level. If using salted butter, reduce added salt slightly.
Milk
Whole milk creates the creamiest frosting, but 2 percent milk or unsweetened almond milk also works well.
Eggs
Bring eggs to room temperature so they blend smoothly into the batter.
Step-by-Step Instructions
Step 1: Prepare the Oven and Pan
Preheat your oven to 350°F. Grease a 9×13 inch baking pan or a rimmed sheet pan. Set aside.
Step 2: Mix Dry Ingredients
In a large bowl, whisk together flour, sugar, baking soda, and salt until evenly combined.
Step 3: Heat Wet Ingredients
In a medium saucepan over medium heat, combine water, butter, and peanut butter. Stir until the butter melts and the mixture is smooth. Do not boil.
Step 4: Combine Batter
Pour the hot peanut butter mixture over the dry ingredients. Stir gently until just combined.
Add eggs and vanilla extract, mixing until smooth and well incorporated.
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 Frosting
While the cake bakes, prepare the frosting. In a saucepan over medium heat, combine butter, peanut butter, and milk. Stir until melted and smooth.
Remove from heat and whisk in powdered sugar and vanilla until creamy.
Step 7: Frost the Cake While Warm
Pour the warm frosting over the hot cake as soon as it comes out of the oven. Spread gently with a spatula. Let the cake cool completely so the frosting can set.
Pro Tips for Success
- Frost the cake while it is still warm so the frosting spreads easily
- Use a whisk for smooth frosting with no lumps
- Do not overmix the batter to keep the cake tender
- Let the cake cool fully before slicing for clean pieces
- Store covered to keep the cake moist
Flavor Variations
- Chocolate Peanut Butter Cake: Add 1/2 cup chocolate chips to the batter
- Crunchy Peanut Butter: Use crunchy peanut butter for added texture
- Peanut Butter and Honey: Replace 1/4 cup sugar with honey
- Peanut Butter Banana: Add 1 cup mashed ripe banana to the batter
- Salted Peanut Butter: Sprinkle flaky salt over the frosting for contrast
Serving Suggestions
This old-fashioned peanut butter cake is delicious on its own, but it also pairs well with:
- A cold glass of milk
- Hot coffee or tea
- A scoop of vanilla ice cream
- Fresh sliced bananas
Serve it as a casual dessert, a lunchbox treat, or a comforting after-dinner sweet.
Storage and Freezing Instructions
Room Temperature
Store covered at room temperature for up to 2 days.
Refrigerator
Store in an airtight container for up to 5 days. Bring to room temperature before serving for best texture.
Freezer
Freeze unfrosted or frosted slices for up to 2 months. Wrap tightly in plastic wrap and foil. Thaw overnight in the refrigerator.
Nutrition Facts (Per Serving)
| Nutrient | Amount |
|---|---|
| Calories | ~430 |
| Protein | ~8 g |
| Carbohydrates | ~52 g |
| Fat | ~22 g |
| Fiber | ~2 g |
| Sodium | ~260 mg |
Nutrition values are estimates and may vary based on ingredients used.
FAQ About Easy Old-Fashioned Peanut Butter Cake
Can I make this cake ahead of time?
Yes. This cake actually tastes better the next day as the flavors settle. Store covered at room temperature or in the refrigerator.
Why is the frosting poured on warm?
Pouring the frosting on while the cake is warm allows it to spread easily and slightly soak into the top, creating a classic old-fashioned texture.
Can I use natural peanut butter?
It is not recommended. Natural peanut butter separates and can affect the cake’s texture and moisture.
Is this cake overly sweet?
No. The peanut butter balances the sweetness, making the cake rich but not cloying.
Can I make this into cupcakes?
Yes. Bake in lined muffin tins at 350°F for 15 to 18 minutes, then frost while warm.
Easy Old-Fashioned Peanut Butter Cake
Equipment
- 9×13-inch baking pan
- mixing bowls
- whisk
- saucepan
- spatula
Ingredients
- 2 cups all-purpose flour
- 2 cups granulated sugar
- 1 tsp baking soda
- 1/2 tsp salt
- 1 cup water
- 1/2 cup unsalted butter
- 1/2 cup creamy peanut butter
- 2 large eggs
- 1 tsp vanilla extract
- 1/2 cup unsalted butter (for frosting)
- 1/2 cup creamy peanut butter (for frosting)
- 1/3 cup milk
- 4 cups powdered sugar
- 1 tsp vanilla extract (for frosting)
Instructions
- Preheat the oven to 350°F and grease a 9×13-inch baking pan.
- In a large bowl, whisk together the flour, sugar, baking soda, and salt.
- In a saucepan over medium heat, combine the water, butter, and peanut butter. Heat until melted and smooth, without boiling.
- Pour the hot peanut butter mixture over the dry ingredients and stir until just combined. Add the eggs and vanilla and mix until smooth.
- Spread the batter evenly in the prepared pan and bake for 20–25 minutes, until a toothpick comes out clean.
- While the cake bakes, heat the butter, peanut butter, and milk for the frosting until melted. Remove from heat and whisk in powdered sugar and vanilla.
- Pour the warm frosting over the hot cake, spread gently, and let cool completely before slicing.
Notes
Nutrition
Final Thoughts
This easy old-fashioned peanut butter cake recipe proves that the best desserts are often the simplest ones. With a tender crumb, bold peanut butter flavor, and a smooth frosting that melts into every bite, this cake delivers comfort and nostalgia in the best possible way. It is the kind of recipe you will make again and again, whether for family, friends, or just because you need a little something sweet.
