Plantain and Caramel Cake

This is genuinely one of the most fun recipes I’ve written and tested in a while. Plantain cake with brown sugar Swiss meringue buttercream, homemade caramel and crunchy plantain chips. I mean, COME ON. Lemme walk you through the process because, as with most of my recipes, this started with me being hungry on the internet.

I was scrolling on TikTok one night, as I always do, when a post from Butter and Spice Bakeshop popped up on my feed. It was a plantain cake layered with brown butter buttercream, caramel and crunchy plantain chips and WOW. My mouth instantly started salivating. I immediately jumped onto their page ready to place an order, only to discover they were based across the pond. Ouch.

So naturally, I took it upon myself to recreate something similar for us UK girlies over here, but of course, I had to give it a little Remi twist.

Developing the Perfect Plantain Cake

When I started thinking about the actual sponge, my mind immediately went to my Brown Butter Banana Bread. You guys ADORE that recipe, and for good reason. It’s soft, moist, fluffy and has the most incredible nutty flavour from the brown butter, so I knew it would be the perfect baseline for developing this plantain cake.

Plantain and banana might be related, but they behave slightly differently when baked. Plantain has a starchier texture and a slightly less sweet flavour, particularly if it isn’t extremely ripe, so getting enough moisture into the sponge was really important.

For this recipe, you want very ripe plantains. I’m talking yellow with lots of black spots, or even almost completely black. This is not the time for a firm green plantain! As plantains ripen, their starches convert into sugars, giving us a softer texture and much more natural sweetness.

And then, obviously, we’re browning our butter.

If you’ve made my Brown Butter Banana Bread or my Chewy Chocolate Chip Cookies, you’ll know how much I LOVE brown butter. Browning butter essentially means cooking it past the melting stage until the milk solids toast and caramelise. The result is this deeply nutty, almost caramel-like flavour that makes people taste your cake and immediately ask, “Wait, what is IN this?”

The trick is to keep an eye on it. Your butter will melt, become incredibly noisy while the water evaporates, foam up and then eventually those milk solids will begin turning golden brown. Once you can smell that gorgeous nutty aroma, remove it from the heat and pour it into another bowl so it doesn’t continue cooking in the hot pan.

For this plantain cake, I use both brown butter and oil. The brown butter is there for FLAVOUR, while the oil helps the cake stay beautifully moist even after it has been refrigerated.

Once your brown butter has cooled, the cake itself comes together really quickly. No complicated mixing methods, just a gorgeous plantain cake batter that bakes into a soft, moist sponge ready for all those delicious layers.

Brown Sugar Swiss Meringue Buttercream

Now we need to talk about this brown sugar Swiss meringue buttercream because I know some of you are going to read those words and immediately think, absolutely not.

But TRUST ME.

Swiss meringue buttercream sounds much scarier than it actually is. It’s also one of those recipes where you really do have to trust the process because at several points you may look into your mixing bowl and think you’ve completely ruined it.

You probably haven’t.

Swiss meringue buttercream starts by gently heating egg whites and sugar together over a bain-marie. You want the sugar to completely dissolve into the egg whites. If you rub a little mixture between your fingers, you shouldn’t be able to feel any sugar granules.

Once dissolved, transfer it to your mixer and whisk until you have a thick, glossy meringue with stiff peaks. More importantly, the bowl needs to have cooled down before you start adding the butter. If your meringue is still hot, you’re essentially throwing butter into a warm mixture and expecting it not to melt. We don't want buttercream soup!

Once the bowl feels cool, start adding your softened butter gradually while continuing to whisk.

This is where things can get interesting.

Your buttercream might suddenly look curdled. It might look split. It might look like scrambled eggs. KEEP WHISKING. Nine times out of ten, Swiss meringue buttercream just needs more time.

If it looks curdled, it is usually too cold. You can gently warm the outside of the mixing bowl and continue whisking until it emulsifies.

If it looks soupy, however, it’s usually too warm.

And I’m actually writing this recipe during a heatwave, so I can tell you firsthand that once all your butter has been added, you may STILL be staring at a bowl of soup wondering where it all went wrong.

Pop the entire bowl into the fridge for around 30 minutes, then bring it back out and whip it again. Once the butter has had a chance to firm up slightly, everything should come together into that silky, smooth buttercream we’re looking for.

Swiss meringue buttercream really is a lesson in trusting the process.

If you want to practise the technique, my Ultimate Vanilla Cake also uses Swiss meringue buttercream and has plenty of tips for creating that smooth, bakery-style finish.

Do NOT Put Hot Caramel on Buttercream!

Finally, we have the caramel.

PLEASE make this in advance.

Hot caramel and buttercream are a disaster waiting to happen. You could make the most beautiful cake of your life, spoon warm caramel between the layers and watch your buttercream melt before your eyes. We don't need that stress.

I actually recommend making the caramel the day before if you can. My Easy Homemade Caramel Recipe uses sugar, cream, butter, vanilla and salt to create a rich, glossy caramel that thickens beautifully as it cools.

Once completely cooled, it is perfect for layering between the plantain cake and brown sugar Swiss meringue buttercream.

Then comes my favourite part: the crunchy plantain chips.

They add that little salty crunch that this cake desperately needs. You’ve got soft plantain sponge, silky buttercream and sticky caramel, so having something crunchy running through the cake completely changes the eating experience. Sweet, salty, soft, creamy, sticky AND crunchy. Everything has a purpose.

The Ultimate Plantain Cake

The final result is honestly ridiculous.

You get a beautifully moist brown butter plantain cake, silky brown sugar Swiss meringue buttercream, rich homemade caramel and those crunchy plantain chips bringing everything together.

It has familiar flavours, but in a completely different format. The plantain brings that gorgeous natural sweetness, brown butter adds nuttiness, brown sugar gives the buttercream a deeper caramel flavour and the salted caramel ties the whole thing together.

If you love the caramelised, nutty flavours in my Brown Butter Banana Bread, this is basically its dressed-up celebration cake cousin.

And that is exactly what I love about recipe development. Sometimes inspiration comes from a restaurant, sometimes from travelling and sometimes from scrolling TikTok at night and becoming devastated that the cake you want is thousands of miles away.

So thank you, Butter and Spice Bakeshop, for sending me into the kitchen because this one is GOOD.

Plantain cake. Brown sugar Swiss meringue buttercream. Homemade caramel. Crunchy plantain chips.

Need I say more?