If you’re a chocolate-peanut butter fan, then you have to try this easy malted chocolate cake with peanut butter frosting! This moist, one-bowl cake is made from scratch but it’s honestly just as simple as whipping up boxed mix. Then, it’s topped with fluffy, whipped peanut butter frosting and flaky salt for a pop of flavor. Serve this for a birthday, a party, or as a casual, after-work snack!

A sliced malted chocolate cake with peanut butter frosting on a white plate next to a white bowl of cocoa, a wood bowl of salt, and a green linen with a white background.

Some days, I wake up on time, hit the gym, and drink a liter of water before it’s even 7am. Other days, I wake up and need cake for breakfast. This little snack cake is the exact recipe I pull out on the cake mornings. It has the richness of black velvet cake with the nostalgia of yellow cupcakes with chocolate frosting.

The homemade chocolate cake is one I have been making 5ever. It’s my go-to because it’s ridiculously easy and one-bowl. The PB frosting is one I learned how to make when I was a teenager in pastry school about 12 years ago, and I’ve held on to it ever since. But in this recipe, we’re adding malted milk powder to both the cake and frosting for some milk shake vibes! Let’s make it.

We need to talk about this cake

I know we all love a gorgeous layered cake, but that’s not what we’re doing today. Sometimes, you just need a simple gal and that’s what we have in this cake – she’s:

  • Easy & one-bowl – less dishes, bless.
  • Quick to make – nothing fussy and tastes way better than boxed chocolate cake.
  • The perfect chocolate cake combo – what’s not to love about PB and chocolate?
  • A snack…cake, that is – we all love a snack cake situation and this one is the best!
A grey bowl of flour and cocoa powder next to white bowls of sugar, nut butter, milk, milk powder, a green linen, and other baking ingredients on a white speckled background.

The ingredient list

  • Sugar – just regular white sugar here to sweeten the cake. Nothing fancy!
  • Buttermilk – the acidity in buttermilk will activate the baking soda, creating a light and fluffy cake. I recommend full-fat buttermilk for the best results.
  • Neutral oil – since this is an oil-based cake, we need a neutral oil as our fat source. I use canola but vegetable is good too.
  • Eggs – to add structure and flavor to the cake.
  • Vanilla extract – I always add a bit of vanilla extract to give the cake extra flavor (and because vanilla is just the best!)
  • All-purpose flour – flour gives the cake structure. Regular all-purpose works great for this recipe.
  • Malted milk powder – malted milk powder is what gives Whoppers or milkshakes their classic flavor. Which makes it perfect for chocolate cake! You can find it in the baking aisle or powdered milk aisle of most grocery stores or online. Also, you don’t need malted milk powder to make this cake – more on this later.
  • Cocoa powder – for all that chocolatey flavor! I personally like Dutch cocoa for its richness, but any cocoa you have works great.
  • Baking soda – this will give us a nice spongy texture.
  • Kosher salt – to offset the sweetness just a bit.
  • Unsalted butter – this will make up the base of our frosting. Make sure it’s softened!
  • Peanut butter – as much as I love “100% peanuts” peanut butter, this is not the place for it. Get the classic, super sweet PB you had in sandwiches as a kid.
  • Powdered sugar – to add sweetness and volume to the peanut butter buttercream.
  • Flaky salt – for finishing the cake. Optional but recommended!

How to make this recipe

This is the best recipe for chocolate cake with PB buttercream. Let’s talk about how to make this homemade cake in 3 simple steps. (P.S. find the step-by-step video in the recipe card!)

One bowl malted chocolate cake

Steps to making one bowl chocolate cake batter. In step one, hands are mixing wet ingredients in a white bowl. In step 2, hands are whisking flour and cocoa in the white bowl. In step 3, the woman is pouring the batter in a cake pan on a white counter.
  1. First, whisk together the sugar, buttermilk, oil, eggs, and vanilla extract until smooth.
  2. Then, add the flour, malted milk powder, cocoa powder, baking soda, and Kosher salt. Whisk just until the batter comes together.
  3. Pour the chocolate batter into a prepared 9” springform pan. Bake at 350°F for 30-40 minutes.
  4. Once the cake is done, remove it from the pan. Then, let the cake cool completely on a wire rack.

Fluffy whipped peanut butter frosting

Steps to making frosting. In the first photo, butter and peanut butter are being mixed in a white bowl next to a green linen on a white counter. In photo two, hands are pouring malt powder into the bowl. In step 3, a mixer is mixing the frosting together.
  1. While the cake cools, make the frosting. First, beat the butter and peanut butter until it’s smooth.
  2. Next, add the powdered sugar and malted milk powder. Mix until you have a thick buttercream.
  3. Then, add vanilla extract, milk, and a pinch of salt. Whip the frosting until it’s light and fluffy.

Frost & decorate

Steps to assembling a cake. In photo one, a woman is frosting a cake on a white plate with a white background. In photo two, the woman is sprinkling flaky salt on the cake.
  1. Once the cake is cool, it’s time to frost and decorate! Dollop the frosting on top of the cake and use an offset spatula or butter knife to frost the cake.
  2. Lastly, sprinkle some flaky salt over the top. Slice and enjoy!

What pan should I use?

One-layer cake/sheet cake: For this recipe, you’ll want to use a 9” springform pan. The pan needs tall edges so that the cake doesn’t overflow. You can also use an 8×8” square pan, which is the same volume as a 9” round cake pan.

Two-layer cake: If you don’t have a springform pan (or just want a taller cake), you can make a double layer cake instead. Just divide the batter between two 8” round cake pans. Bake for 22-26 minutes, until an inserted toothpick comes out clean. Also, double the frosting so that it coats the outside!

Cupcakes: Divide the batter evenly between 16 cupcake liners. Bake for 14-16 minutes until an inserted toothpick comes out clean. You will want to double the frosting if you want to pipe the buttercream on top!

Other helpful tools

When to serve this cake

A lot of the times, I make this cake ‘just because’. It’s the perfect cake to slice and snack on over a long weekend or for movie nights with friends. But, it’s also amazing for:

  • Birthday parties
  • Potlucks or BBQs
  • Dinner parties
  • Casual get-togethers

Decoration ideas

If flaky salt isn’t your thing, all good. You can decorate the cake with all kinds of fun stuff!

  • Reese’s (or your PB cups of choice) on top – chop them or keep them whole.
  • Pipe swirls of frosting on the edges of the cake with a piping bag & tip.
  • Add some fun sprinkles on top!
A sliced malted chocolate cake with peanut butter frosting on a white plate next to an emerald green linen, a white bowl of cocoa, and a wood bowl of salt on a white table.

Storing, freezing, & make-ahead

Store: To store leftover cake, place it on a plate and cover it with a cake dome. Or, place individual slices of cake in an airtight container. Store at room temperature for up to 3 days.

Freeze: To freeze the cake, place the cake on a sheet pan and freeze for 3-4 hours until completely firm. Wrap the cake in a layer of plastic wrap and then a layer of aluminum foil. Freeze for up to 3 months and thaw, uncovered, at room temperature for at least 2 hours. You can also freeze individual slices.

Make-ahead: To make this recipe in advance, I recommend freezing the unfrosted cake and decorating later. To freeze the cake, follow the same directions above. Once the cake is thawed, ice the cake and serve. The frosting can be made up to 3 days in advance.

Recipe tips & tricks

  • Use room temperature ingredients so everything mixes thoroughly. Bring the eggs, butter, and buttermilk to room temp for 30-60 minutes.
  • Properly measure the flour to prevent a dry cake. First, fluff it with a whisk and then spoon the fluffed flour into a measuring cup. Level it off without packing the flour in.
  • Sift the dry ingredients if you notice any lumps in the flour or cocoa powder. This will make for a more even batter.
  • Don’t over-mix the batter! Otherwise, the cake will come out tough and dry.
  • Bake the cake just until an inserted toothpick has a few crumbs. This will make for a super moist, fluffy cake!

FAQs

Why is my frosting runny?

The frosting will sometimes get a bit runny if your kitchen is too hot or humid. To fix it, just pop it in the fridge to firm up a bit! Also, avoid using ‘natural’ peanut butter, which is a bit runnier and oily naturally. Instead, use a classic creamy PB.

Can’t I just add PB to store-bought icing?

Store-bought icing is already very thick, so adding peanut butter will affect the texture and make for a super dense frosting. Honestly, making homemade frosting is so easy and tastes way better anyways!

What makes this cake moist & fluffy?

The oil in this recipe will already make this cake nice and moist. But, you can also guarantee a nice fluffy cake by measuring the ingredients properly, especially the flour. Also, don’t over-mix or over-bake the cake, and it’ll come out perfectly.

What if my cake has a dome?

This cake will naturally rise and have a bit of a dome. If it bothers you, just slice it off to level the cake. If you don’t care, plop the frosting on top and swirl away!

A slice of one bowl chocolate cake with peanut butter frosting on a white plate next to a whole cake, glasses of milk, and green napkin with a white background.

More cake recipes to try!

Sour Cream Lemon Pound Cake with Blackberry Icing
Chocolate Stout Cake with Irish Cream Cheese Frosting
Ricotta Strawberry Lemon Cake

If you make this recipe, I would love it if you left a star rating and review! I read every single comment and love hearing what you think about my recipes. Thank you for supporting Sunday Table!


A slice of chocolate cake with peanut butter icing on a white plate next to a green linen with a white background.
5 from 1 vote

Malted Chocolate Cake with Peanut Butter Frosting

Yield: 8 slices
Prep Time: 20 minutes
Cook Time: 40 minutes
Total Time: 1 hour
This cake is for you chocolate-peanut butter fans! With moist, one-bowl, malted chocolate cake and fluffy peanut butter frosting, this is the perfect dessert for birthdays, parties, or as a casual, after-work snack. It's the absolute best!

Ingredients

Malted Chocolate Cake

  • 1 1/4 cups sugar
  • 1 cup buttermilk
  • 2/3 cup neutral oil (canola or vegetable)
  • 2 large eggs, room temperature
  • 1 1/2 teaspoons vanilla extract
  • 1 1/4 cups all-purpose flour
  • 1/4 cup malted milk powder
  • 1/2 cup cocoa powder
  • 1 1/4 teaspoons baking soda
  • 1/2 teaspoon Kosher salt

Fluffy Peanut Butter Frosting

  • 1/2 cup unsalted butter, softened
  • 1/2 cup creamy peanut butter
  • 1 cup powdered sugar
  • 1/2 cup malted milk powder
  • 1 teaspoon vanilla extract
  • 1 Tablespoon whole milk (plus more, as needed)
  • Pinch of Kosher salt
  • Flaky salt, for serving

Equipment

  • 9'' springform pan (or 8×8 square pan)
  • Parchment paper

Instructions 

Malted Chocolate Cake

  • Preheat the oven to 350°F. Grease a 9'' springform pan with baking spray or neutral oil and line with parchment paper.
  • In a large bowl, combine the sugar, buttermilk, vegetable oil, eggs, and vanilla extract. Whisk until smooth.
  • Add the flour, malted milk powder, cocoa powder, baking soda, and Kosher salt. Whisk just until the batter is combined (don't over-mix!).
  • Pour the batter into the prepared springform pan. Bake for 30-35 minutes until an inserted toothpick has a few moist crumbs on it. Let the cake cool in the pan for about 10 minutes. Then, use a butter knife to loosen the edges of the cake from the pan. Flip onto a wire rack and cook completely.

Fluffy Peanut Butter Frosting

  • In a large bowl, beat the butter and peanut butter together until the mixture is smooth.
  • Add the powdered sugar and malted milk powder. Mix until the frosting is thick. Then, add the vanilla extract, milk, and a pinch of salt. Beat the mixture until it's very fluffy and whipped, 3-4 minutes. Add more milk to thin the buttercream, if necessary.

Assemble

  • Once the cake is cooled, you're ready to assemble! If the cake has a dome, slice it off to level the cake (totally optional, this is only for aesthetics).
  • Dollop the frosting on top of the cake and use an offset spatula or butter knife to frost the top of the cake. Use the tip of the offset spatula to create swirls.
  • Finish the cake with a sprinkle of flaky salt. Or, decorate as desired. Slice and enjoy!

Notes

To make homemade buttermilk, measure out 1 cup of whole milk. Remove 1 Tablespoon of milk and then add 1 Tablespoon of white vinegar. Whisk and let it sit for 5-10 minutes until it’s thickened and slightly curdled.
If you don’t have malted milk powder (or can’t find it), you can replace the malted milk powder with all-purpose flour in the cake and powdered sugar in the frosting.
This cake will make 8 large servings or 16 smaller servings.
Cuisine: American
Course: Dessert
Serving: 1slice, Calories: 670kcal, Carbohydrates: 71.6g, Protein: 10.6g, Fat: 41g, Saturated Fat: 11.9g, Cholesterol: 76mg, Sodium: 570mg, Potassium: 375mg, Fiber: 3.1g, Sugar: 51.8g, Calcium: 86mg, Iron: 3mg
Did you make this recipe?Tag @sundaytable.co on Instagram!

HEY, I’M SARA LYNN HUNT-BROKA!
I am the writer, photographer, and late-night recipe developer behind Sunday Table! Since 2012, I have been sharing cozy recipes to inspire others to find a love of cooking and entertaining for loved ones. Learning from my family who loves a good get-together, my crowd-pleasing recipes are comforting, elevated, and always made-from-scratch. Pull up a chair and let’s hang!

xo Sara Lynn

Song of the day – Take it Easy by White Denim