This banana cake is like heaven in a slice! Not only does it have two layers of moist banana cake, but it’s also smothered in creamy peanut butter chocolate frosting. Basically all three of the best flavors wrapped up in one cake!

the inside of a sliced banana layer cake

How to make banana cake

No only does this cake have banana, peanut butter, AND chocolate…but the cake batter is mixed by hand! We love a good quick and easy cake recipe.

The batter starts by whisking together melted butter, sugar, and brown sugar. The melted butter adds so much richness and flavor, while the brown sugar adds a little extra moisture!

Then sour cream, eggs, vanilla, and finely mashed banana are added. Sour cream adds yet another layer of moisture but its tangy flavor also helps balance out the sweet bananas. Of course for the best flavor and cake texture, use super ripe brown bananas and mash them up as fine as possible!

Then half of the dry ingredients are mixed in. This includes flour, baking powder, baking soda, and salt. But to prevent the batter from clumping up, milk is mixed in before the rest of the dry ingredients are added.

The batter turns into the perfect thick pudding-like consistency that produces a dense and moist but tender banana cake.

Tips for making this banana cake recipe

Bananas – The riper the bananas, the better! Ripe bananas have SO much more flavor and help to create a really moist and tender cake texture. Also make sure to measure the banana to exactly 1 1/2 cups.
Flour – If possible, weigh the flour with a food scale. Otherwise, spoon the flour into the measuring cup and level it off with a flat edge. NEVER scoop directly into the flour as this packs the flour down into the cup, leaving you with way too much added flour.
Mixing – Once the dry ingredients are added to the batter, take the mixing nice and slow. Over mixing can lead to a tough cake with a sunken center. At this point, I like to switch to a rubber spatula to further prevent over mixing.
Cake Strips – If you have them, cake strips allow these cakes to bake incredibly even with the same consistency from edge to center. If you don’t have cake strips, that’s totally fine. But these little pieces of cloth make a huge difference in cake baking!

the top of a banana cake with a swirl of peanut butter chocolate frosting

How to make peanut butter chocolate frosting

This might just be my new favorite frosting recipe. The peanut butter makes it SO rich and smooth and the chocolate prevents it from being too sweet.

To make this frosting, start with room temperature butter. This is key to making a super smooth buttercream!

The butter is mixed until smooth, and then the peanut butter goes in. This is your standard creamy butter like Jif or Skippy. Don’t use natural here as the excess oils will create a thin buttercream.

After the butter and peanut butter, powdered sugar is added to both sweeten and thicken the buttercream. It’s added one cup at a time and be careful not to pack it into the cup. Just like flour, powdered sugar must be spooned into the cup and leveled off.

Once the sugar is mixed in, the chocolate is next. Regular unsweetened cocoa powder is used to give this frosting its chocolatey taste. But, regular cocoa powder tends to be a bit clumpy so make sure to sift it in.

At this point, the buttercream will appear very thick. Vanilla and milk are added for flavor and to help smooth out the buttercream. In the end, you want a buttercream that has a smooth and silky consistency but is still thick enough to hold its shape.

slices of banana cake layer in their sides

How to frost banana cake

Cake strips are supposed to prevent cakes from baking with an uneven top. While that works most of the time, it’s not super effective ALL of the time. This cake bakes incredibly even BUT it’s still just a tad bit domed on top.

So before frosting, make sure to level off the cakes. The easiest and fastest way is to use a cake leveler. Otherwise, a large knife will also do the job.

Once the cakes are leveled, it’s time to add the frosting! First, spread about a cups-worth of frosting between the two layers. Spread it as smooth and as level as possible and allow it to reach over the edges of the cake.

Lay the second layer on top of the first layer but place it upside down so the bottom of the cake is now the top. The bottom of the cake is completely sealed, whereas the top is porous since it was leveled. Stacking the cakes this way is just extra insurance to prevent it from drying out too fast, while also providing a super smooth surface.

Smother the entire cake in the remaining buttercream. Yep, no crumb coat here! This banana cake bakes with a tight crumb and smooth sides so there’s just no need for it.

Top with chopped peanuts, banana chips, chocolate shavings, or sprinkles and dig in!

a bite taken from a slice of banana cake

For more banana recipes, check out my:

Make sure to tag me @butternutbakery on Instagram if you make this banana cake. I love seeing my recipes come to life in YOUR kitchen! To pin this recipe and save it for later, you can use the button on the recipe card, the buttons above or below this post, or on any of the photos above. Happy baking!