banana cake with peanut butter frosting and chocolate sauce

I decided to go all out for you guys, given that this is my last week in Texas. So it had to be big, it had to be sweet, and there had to be peanut butter in there somewhere. I give you banana bread made into a cake covered with peanut butter frosting and drowned in chocolate sauce. Voilà!

The rest of this week is going to be spent packing my life up into boxes and suitcases AGAIN! Most of the props I have accumulated are going to stay in Texas for the moment. I am dreading packing them up. If you know me, then you might know that when it comes to things I love, I am really paranoid about breaking them. So lots of newspaper and bubble wrap is going to be needed.

I’m so excited to see my parents and my furry friend Kit Kat. It has been 3 whole months! Also weirdly looking forward to grey cloudy skies and rain. Real Autumn weather. And before you know it it’s going to be Christmas! What are you planning this year? Is it going to be turkey, or beef wellington, or goose or pheasant or are you vegetarian?? So many options!

Anyway, before I get too carried away. Back to the enormous cake! Naturally, bananas and peanut butter are a match made in heaven. The dark chocolate sauce cuts through the sweetness perfectly. You could definitely halve this recipe if you only have a few mouths to feed, but be warned. It’s highly addictive! I would recommend a glass of ice cold milk on the side. Perfect.

I haven’t used peanut butter in my baking in a while now. A few months ago I went through a phase where I literally made peanut butter pie twice a week. I know, I’m a terrible person. My boyfriend gets the blame for introducing me to the idea. These Americans, they sure know how to make food indulgent! Says the girl who just made this cake. Pure hypocrisy. Make the cake. Indulge. Eat peanut butter. Be happy.

PS – I topped this cake with the coconut chocolate sauce that I made with the pandan ice cream. Get the recipe here!


  • Serves: 12 slices
  • Time:
    • Prep: 20 mins
    • Cook: 75 mins
    • Passive: 60 mins


  • cake
    • 3 1/2 cups all purpose flour
    • 2 teaspoons baking powder
    • 1 1/2 teaspoons baking soda
    • 1 teaspoon kosher salt
    • 2 sticks butter at room temperature
    • 2 tbsp tuaca dark rum or bourbon will work well too
    • 2 cups mashed ripe banana
    • 1 cup sugar
    • 1 cup light brown sugar
    • 4 large eggs
    • 6 tablespoons sour cream
    • 2 teaspoons vanilla extract
  • frosting
    • 1 cup smooth peanut butter
    • 1 cup room temperature butter
    • 3 cups powdered sugar sift after measuring
    • 1 teaspoon vanilla extract
    • 3 tablespoons heavy cream
  • simple syrup
    • 1/3 cup water
    • 1/3 cup sugar


  1. Begin by making the cake. Preheat the oven to 325f (see notes). Take a 10-inch cake tin (I used springform) and line with parchment paper. You will want the parchment to come up beyond the top of the sides of the pan as the cake puffs up quite a lot in the oven.
  2. Next, using an electric whisk, beat the butter and sugars together until they are fluffy. Add the eggs, 1 at a time, beating well and scraping down the sides of the bowl between each addition.
  3. Add the banana, tuaca, sour cream and vanilla extract. Beat to combine. Don’t worry if your mixture is looking a bit weird at this stage. It will come together once you add the dry ingredients.
  4. In a separate bowl, sift together the flour, baking powder and baking soda. Add the salt and whisk briefly to combine everything. Add this, in 3 additions, to the wet ingredients.
  5. Once everything is well combined, pour the cake batter into the cake tin and bake for about 1 hour and 15 minutes. Start checking for doneness at 1 hour. To check to see if the cake is done, insert a metal skewer into the middle. If it comes out clean, the cake is done!
  6. Leave the cake to cool to room temperature. Meanwhile, get your butter out of the fridge to make the frosting. Once the cake has reached room temperature pop it in the fridge, as it is much easier to ice a cold cake.
  7. While the butter is coming to room temperature, make the simple syrup by combining the sugar and water in a small saucepan. Over a medium high heat, stir until all the sugar has dissolved. Once cool, pour into a squeezy bottle or small jug.
  8. Now, onto the frosting. Using the paddle attachment on your stand mixer (or an electric hand whisk), beat the butter for a few minutes until it is pale and smooth. Add the peanut butter and beat again until well combined. Add the vanilla extract and 1 cup of powdered sugar. Beat to combine, then add 1 tablespoon of heavy cream and beat. Repeat until all the powdered sugar and heavy cream has been added.
  9. Whip the frosting for 2 minutes on a high speed until it is nice and fluffy, then fill your piping bag and set it aside in the fridge. Remove the cake from the fridge and get ready to slice it. You will need a bread knife, several toothpicks and a ruler.
  10. Begin by trimming off the dome on top of the cake so you have a flat surface to work with. Eat the crumbs using what’s left in the frosting bowl. Using the ruler, measure halfway up the cake and insert a toothpick. Repeat this several times around the outside of the cake until it is wearing a toothpick choker.
  11. Use the toothpicks to guide the knife as you cut around the cake, then work your way into the middle. Once you have your two cake layers, it’s frosting time!
  12. Pipe a little smudge of frosting onto your plate or cakestand so the bottom piece of the cake sticks to it. Then, take the simple syrup and drizzle it over the cake to keep it moist. Fill with a layer of frosting (about 3/4 cm) and drizzle with chocolate sauce. Add the top layer of the cake and repeat the simple syrup and frosting. Frost the sides of the cake, using an offset spatula to smooth the surface. Pour chocolate sauce onto the cake, letting it drizzle down the sides and pool into delicious puddles on the cake stand. Add sprinkles if desired.
  13. Chill for about 15 minutes to firm up the chocolate, then slice, dig in and enjoy!


I like to use the convection bake setting on my oven to get a more even bake on a big cake like this. The fan circulates air around the oven more efficiently so things tend to cook quicker and more evenly. If, however, you want to bake on your regular setting, preheat your oven to 350f and be aware that your cake may take a little longer to cook.

You can find the chocolate sauce recipe in the PS at the bottom of the post!

Written on October 10, 2017