Peanut Butter Birthday Cake
Get ready to celebrate life with this sweet and salty Peanut Butter Birthday Cake! It’s a 4 inch cake recipe featuring 3 mini layers of homemade peanut butter cake decorated with peanut butter frosting.

Today is my birthday, so happy birthday to me! (cue the confetti and horns).
Of course every birthday needs cake, so I opted to bake this Peanut Butter Birthday Cake from scratch with the dreamiest peanut butter frosting you can imagine.
It’s a sweet and salty 4 inch cake recipe that I turned into a nutty mini layer cake for this special occasion.
You don’t even need to have killer decorating skills because all you need to do is stick a peanut butter cup into the top. Voila – instant cake topper.
Peanut butter cake isn’t something you see often. Usually if there’s peanut butter involved, it’s my small chocolate cake recipe with peanut butter frosting or my chocolate peanut butter cake with its peanut butter filling.
With this peanut butter cake recipe, I wanted peanut butter to be the star.
Of course I couldn’t resist adding some chocolate with chopped peanut butter cups.
And because this is a peanut butter birthday cake after all, don’t forget to serve it with some peanut butter ice cream!

Ingredients For Peanut Butter Birthday Cake
Here’s what you need to make your peanut butter layer cake:
- All purpose flour: Standard baking flour using to balance the wet ingredients
- Baking powder: Leavening agent so your cake layers rise
- Salt: Enhances the flavor of the batter so it’s not bland
- Butter: Adds flavor and helps the cake rise from its steam when it melts, trapping carbon dioxide in the batter as it bakes. This creates a tender crumb texture.
- Peanut butter: Made with smooth processed peanut butter as it has the most consistent results. Natural peanut butter varies by brand.
- Sugar: Sweetens the cake and gives it a soft cake texture
- Egg: Provides structure, moisture, and leavening to the cake
- Vanilla: Brings out the peanut butter flavor even more
- Milk: Helps moisten the cake
- Peanut butter chips: An extra burst of peanut butter flavor. You can also use chopped peanut butter cups or semisweet chocolate chips

What pan do I need for a mini layer cake?
This homemade peanut butter cake is baked in three 4 inch springform pans.
If you don’t have 4 inch pans, you can put all of the batter into one 6 inch cake pan.

How To Make Peanut Butter Birthday Cake
Here’s how to make your peanut butter mini layer cake:
- Whisk together flour, baking powder, and salt.
- Cream together butter, peanut butter, and sugar.
- Beat in egg and vanilla.
- Add flour mixture alternated with the milk then stir in peanut butter chips.
- Bake at 350F for 20-25 minutes or until a toothpick comes out clean.
Store unfrosted cake for up to 2 days at room temperature.
Once frosted, cover and store at room temperature for up to 2 days (buttercream only) or in the refrigerator for up to 1 week (buttercream, cream cheese, and ganache).
For best results, let the refrigerated cake sit at room temperature 15-30 minutes before serving.

Frostings For Peanut Butter Cake
As mentioned earlier, I frosted my peanut butter birthday cake with peanut butter buttercream.
However if that’s too sweet for you, you can make tangy peanut butter cream cheese frosting or traditional cream cheese frosting instead.
To make a chocolate peanut butter birthday cake, use chocolate frosting or chocolate cream cheese frosting.
You can also cover the entire cake with chocolate ganache.
If you don’t want traditional frosting at all, you can go with a lighter option such as peanut butter whipped cream, chocolate whipped cream, or cream cheese whipped cream.

More 4 Inch Cake Pan Recipes
Now that you have your 4 inch cake pans, you can make more mini desserts including:

Peanut Butter Birthday Cake
Get ready to celebrate life with this sweet and salty Peanut Butter Birthday Cake! It’s a 4 inch cake recipe featuring 3 mini layers of homemade peanut butter cake decorated with peanut butter frosting.
Ingredients
- 1/2 cup all-purpose flour, sifted
- 1/4 teaspoon baking powder
- 1/8 teaspoon table salt
- 1/4 cup (2 ounces or 4 tablespoons) unsalted butter, softened
- 1/4 cup creamy processed peanut butter (not natural)
- 1/2 cup granulated sugar
- 1 large egg, room temperature
- 1 teaspoon vanilla extract
- 6 tablespoons whole milk, room temperature
- 1/2 cup peanut butter chips, chopped peanut butter cups, or semisweet chocolate chips
- Peanut butter cups, for garnish
Frosting Options (Pick One)
Instructions
- Preheat oven to 350F. Lightly grease three 4 inch springform pans and wrap the outside in aluminum foil (to help prevent leaks).
You can also grease one 6x2 round cake pan and line with parchment paper. - In a medium bowl, whisk together the flour, baking powder, and salt.
- In a large mixing bowl on medium-high speed (with paddle attachment if using stand mixer), beat together the butter, peanut butter, and sugar until light and creamy, about 1 minute.
- Scrape down the bowl then beat in the egg and vanilla.
- Turn the speed down to low then add the flour mixture alternately with the milk, adding the flour in 3 additions and the milk in 2 additions (begin and end with dry ingredients). Do not overbeat. Stir in the peanut butter chips.
- Divide the batter evenly among the three pans. Bake 20-25 minutes or until a toothpick inserted in the middle comes out clean. Cool completely.
- While the cakes are cooling, make frosting of choice.
- Remove the cakes from the pan. If the cakes are round on top, cut the tops of the cake so they are flat for stacking. Place one cake layer on cake stand or plate. Add some of the frosting then top with another cake layer. Repeat with the remaining frosting and cake. Garnish with peanut butter cups.
Cover and store the frosted cake at room temperature for up to 2 days (buttercream only) or in the refrigerator for up to 1 week (buttercream, cream cheese, and ganache). For best results, let the refrigerated cake sit at room temperature 15-30 minutes before serving.
Notes
- For more 4 inch recipes, check out Mini Chocolate Guinness Cake, Mini German Chocolate Cake, and 4 Inch Cheesecake.
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Happy birthday to you!
Thank you!
Can I double this recipe to make 8 inch cake.
I haven’t made it in an 8 inch pan, but if I had to guess: One 4 inch springform pan holds 1 1/4 cups. Three pans = 3 3/4 cups. A 8 x 1/2 inch round pan is 4 cups. Based on that, I would guess you wouldn’t need to double it. It would probably be a little on the thin side.
Happy birthday to you! I was able to print this out and I can’t wait to make it!!!
Thank you! And enjoy
Thanks for the mini cake recipe. Those are 2 of my favorite flavors. As soon as I finish the Pecan Pie I made yesterday, I’ll make this cake.
Don’t know how to do pictures on the computer, but I’ll tell you if I liked it. How can you ruin those flavor’s though.
Yes, please let me know how you enjoy it!
That is a cute cake – done in 4 inch tins too! Happy belated birthday to you!
Thank you! I knew I didn’t want a big cake plus there’s the cuteness factor ;)
ahhhhhh that peanut butter frosting DOES look dreamy!!!
Makes you want to dive right in :) Thanks, Kayle!
can this be made in 2 6in pans?
The batter will fill up one 6 inch pan, so if you’d like a layer cake, you’ll have to double the recipe.
how long does this take to make?
The times are listed in the recipe card under the recipe title.
Hi! Could I add chocolate chips to this recipe? If so, is there a specific type that you would recommend?
Thanks,
Kim
Yes absolutely! You can either fully replace the peanut butter chips or use half peanut butter, half chocolate. My go-to is semisweet, but dark and milk would work as well.
Would this work in a mini bunt pan (4 x 1.75 inches)?
I don’t have a mini bundt pan to test it. What I do know is a 4 inch springform pan holds roughly 1 1/2 cups batter if you fill it to the very top, so probably 1/2 cup – 3/4 cup to keep the cake batter from overflowing. You’d have to measure how much batter your pan would hold then go from there. My guess is you’ll need more than one mini bundt pan.
Hi! This looks amazing! Can the cake be made in advance (if so, what would be the best way to store it)? Or is it best to make it day of? Thanks!
Yes, you can! If it’s only a few days, you can store it at room temperature. Unfrosted you can wrap each layer in plastic wrap. Frosted you can put in an airtight container. You can also refrigerate it if you think you need more time, like up to a week or so. Let it sit at room temperature about 15-30 minutes before cutting so it “warms” up a bit (cake tastes better at room temperature than cold straight from the fridge). Anything longer, I’d freeze the cake layers then frost on the day of.
Thank you SO much for responding to me so quickly. Timing was perfect as I an trying to make the cake tonight :)
Can you omit the peanut butter chips?
Yes
I made this yesterday in a small pie time (8-9in)
I shared with sme neighbors and now i HAVE to make it again!
Absolutely delicious especially with the buttercream icing!
Quick too!
Glad the pie tin worked out for you!
Have you thought of baking the cake in a half sheet cake pan and using a 4 inch cutter to cut the cakes from it!
If you don’t have 4 inch pans, that could be one way to do it. I don’t like that method because then you have cake scraps leftover.