This easy banana fudge cake with peanut butter frosting might just be the best thing I’ve ever come up with.

Baking is usually what happens when I’m bored or trying to avoid my most disliked household duties.

And the idea for this cake came about after remembering a little hack I tried when I was just out of college and on the tightest of budgets.

Banana Cake On A Budget

I simply had some overripe bananas, a cake mix, and needed to bring something into the newsroom for an office party.

So, I made the cake batter, added mashed bananas, and there you have it…I had a banana cake.

Seems so simple right? But 35 years ago, I was pretty proud of myself for coming up with that little trick!

Banana Cake 2.0

Fast forward to a few weeks ago when I remembered that banana cake as I looked at a bunch of nearly black bananas sitting on my kitchen countertop.

And as I procrastinated a few chores, I decided it was time to take that idea of an easy banana cake to the next level.

So now we have an easy banana fudge cake. And homemade peanut butter frosting.

And I don’t think it’s going to get any better than this!

Banana Fudge Cake With Peanut Butter Frosting

Banana Fudge Cake With Peanut Butter Frosting

Prep Time: 10 minutes
Cook Time: 30 minutes
Additional Time: 10 minutes
Total Time: 50 minutes

This is what happens when I play around with recipes inspired by some of my favorite flavors! Easy banana cake, a layer of fudge, all topped with the most sinful peanut butter buttercream frosting. This would definitely be Elvis approved!


  • 1 box yellow cake mix (eggs/oil/water depends on brand mix you use).
  • eggs
  • vegetable oil (you will use HALF of what cake mix calls for)
  • water
  • 1 1/2 c. mashed ripe bananas
  • 1 jar hot fudge topping
  • For Frosting:
  • 1 c. unsalted butter, softened to room temperature
  • 1 c. CREAMY peanut butter *see note
  • 3 c. powdered sugar
  • 1 tsp. vanilla extract
  • 1/2 tsp. salt
  • 2 tbsp. milk


  1. Preheat oven to 350 degrees. Lightly grease and flour a 13x9 baking pan.
  2. Follow direction on cake mix to prepare batter EXCEPT only use 1/2 of the amount of oil listed.
  3. Add mashed bananas to cake mix batter and incorporate well.
  4. Put batter into 13x9 pan and bake according to box directions.
  5. Let cake cook completely.
  6. Spread hot fudge topping over entire cake.
  7. Frost with peanut butter frosting. (see below)

Peanut Butter Buttercream Frosting:

Cream room temperature butter and peanut butter together in a large bowl until creamy.

Add powdered sugar 1/2 c. at a time on low speed until all is mixed in. Stir in vanilla and salt. Add milk and mix together on medium speed until all is incorporated.


You can cut the amount of oil in half for this recipe because of the addition of the bananas. Bananas add moisture without the fat! I recommend only using creamy peanut butter for this recipe. The chunks in a chunky variety kind of weigh the frosting down. Also, all natural peanut butters don't seem to work well in this recipe either. The oil content doesn't allow the frosting to "bloom."

Cake Recipe Inspirations

The idea for the fudge topping on the cake comes from my chocolate mint grasshopper cake.

I originally thought instead of the peanut butter frosting, a simple whipped topping might do.

But peanut butter and bananas are one of my favorite combinations, and so, the decadent peanut butter frosting became the finishing touch to the easy banana cake.

This easy banana cake is topped with a fudgy spread and peanut butter buttercream frosting!

I love this recipe because it’s easy but seems like a special order bakery type cake.

I used the 13×9 cake pan for ease, but if you really wanted to step this cake up, you could easily make this a layer cake and use the fudge topping as the center icing.

Then smother that cake in the peanut butter frosting.

I think I just talked myself into baking it up right now!

If you love peanut butter and chocolate recipes, here are a few more you might like:


Gluten Free Peanut Blossom Cookies

No Bake Peanut Butter Chocolate Cookies

Let me know when you try this easy banana fudge cake~I can’t wait to hear what your taste buds think!

From my kitchen to yours,


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