Brown Sugar and Rum Banana Foster Cake
This banana foster cake turns the flambéed dessert into a tender, upside-down loaf with a sticky brown sugar rum caramel and a soft, sour-cream crumb. It bakes up with a layer of caramelized bananas on top that soak into the cake as it cools.
It smells like a dessert restaurant the second you pull it from the oven, and that rum glaze runs into every slice.
Why This Banana Foster Cake Works
The cake stays moist for days thanks to a good dose of sour cream and mashed ultra-ripe bananas. The crumb is dense enough to hold the sticky topping but still tender.
The caramel layer is pure bananas foster flavor: butter, dark brown sugar, a splash of dark rum, and a little cream to keep it smooth. Once you invert the cake, that glaze drips down the sides and glazes every slice.
It’s the kind of dessert that feels fancy without a ton of work. A skillet or cake pan, one bowl for the batter, and a quick stovetop caramel get you a showpiece that tastes like you spent hours.
Ingredients
- ½ cup unsalted butter, plus more for the pan: for the caramel.
- ¾ cup packed dark brown sugar: light brown sugar works but dark gives a deeper molasses note.
- 3 tbsp heavy cream: makes the caramel silky and pourable.
- 3 tbsp dark rum, divided: 2 tbsp for the caramel, 1 tbsp for the cake batter.
- Pinch of fine sea salt: cuts the sweetness.
- 2 to 3 ripe bananas, sliced ¼ inch thick: make sure they have plenty of brown spots.
- 1 ½ cups all-purpose flour: spooned and leveled, not scooped.
- 1 tsp baking powder:
- ½ tsp baking soda:
- ½ tsp fine sea salt: for the cake batter.
- ½ cup unsalted butter, melted and cooled slightly: for the cake.
- ¾ cup granulated sugar:
- ¼ cup packed light brown sugar:
- 2 large eggs, at room temperature:
- 1 tsp vanilla extract:
- 1 cup mashed very ripe banana: from about 2 medium bananas.
- ½ cup full-fat sour cream, at room temperature: full fat keeps the cake tender for days.
Variations / Substitutions
- No rum: use 1 tsp rum extract in the caramel and 1 tsp vanilla in the batter, or simply leave it out for an alcohol-free cake.
- Sour cream swap: full-fat Greek yogurt works in the cake batter and delivers a similar moist crumb.
- Brown sugar: if you only have light brown sugar, the caramel will be a touch less molasses-rich but still sticky and good. Coconut sugar works too, though the caramel will be more crumbly.
- Dairy-free: use a good vegan butter and full-fat coconut cream instead of heavy cream and sour cream. The cake will still bake up moist.
- Gluten-free: a cup-for-cup all-purpose gluten-free blend swaps in for the flour without other changes.
If you enjoy boozy banana desserts, try our bananas foster bread pudding or banana rum cake next.
How to Make Banana Foster Cake
Step 1: Simmer the Caramel and Arrange the Bananas
Set a 9-inch round cake pan (at least 2 inches deep) next to the stove. Combine the ½ cup butter, the ¾ cup dark brown sugar, the 3 tbsp heavy cream, and the pinch of salt in a small saucepan over medium heat. Stir until the butter melts and the sugar dissolves, then stop stirring. Let the mixture bubble gently for 2 minutes, until it thickens slightly. Remove from the heat and carefully stir in 2 tbsp of the dark rum. The caramel will sputter a little.
Pour the hot caramel into the ungreased cake pan right away and tilt the pan so it coats the bottom evenly. Lay the banana slices in a single layer over the caramel, pressing them together gently so there are no big gaps. Set the pan aside while you make the batter.
The caramel will start to firm up as it cools, which is exactly what you want. It should be tacky, not hard, when you pour the batter over it later.
Step 2: Mix the Cake Batter
Whisk the 1 ½ cups flour, the 1 tsp baking powder, the ½ tsp baking soda, and the ½ tsp salt together in a medium bowl. In a large bowl, whisk the ½ cup melted butter, the ¾ cup granulated sugar, and the ¼ cup light brown sugar until smooth. Add the 2 eggs one at a time, beating well after each, then mix in the 1 tsp vanilla, the 1 cup mashed banana, the ½ cup sour cream, and the remaining 1 tbsp rum.
Pour the dry ingredients into the wet mixture and fold with a spatula just until the flour disappears. The batter will be thick and a little lumpy, and you should still see a few streaks of flour; overmixing makes the cake tough.
Step 3: Bake the Cake
Preheat the oven to 350°F (175°C) with a rack in the middle. Scrape the cake batter over the bananas and caramel in the pan and spread it to the edges using an offset spatula or the back of a spoon. Smooth the top so the cake rises evenly.
Bake for 30 to 35 minutes, until the top is deep golden and a toothpick inserted in the center comes out with a few moist crumbs attached (no wet batter). The cake will pull away from the sides of the pan just slightly. Let the cake cool in the pan on a wire rack for exactly 10 minutes, not longer, or the caramel will harden and stick.
Step 4: Flip and Serve
Run a thin knife around the edge of the pan to loosen the cake. Place a serving plate upside down over the pan, then, holding both firmly, flip the plate and pan together in one quick motion. Give the bottom of the pan a few gentle taps, then lift the pan away. The caramelized banana layer will be glossy and sticky on top.
Slice and serve while the cake is still warm, maybe with a scoop of vanilla ice cream to catch the drips. The crumb will be tender and the bananas a little boozy, with a deep brown sugar finish.
A Few Tips for Banana Foster Cake
- Don’t overmix. Stir the batter just until the flour is absorbed, then stop. A few small lumps are fine, and they bake out into a tender crumb.
- Cool exactly 10 minutes. Any longer and the caramel will set too firm, making the cake hard to unmold. Any less and the topping might slide off.
- Slice neatly. For party-clean pieces, let the cake cool completely after inverting, then warm individual slices in the microwave for 15 seconds before serving. Warm cake is easier to cut, but a cold cake holds its shape better.
- Boost the rum flavor. Brush the warm, inverted cake with an extra tablespoon of dark rum right after flipping. It soaks right in and intensifies that bananas foster taste.
Bake times by pan:
| Pan | Bake Time |
|---|---|
| 9-inch round, 2 inches deep | 30–35 minutes |
| 8-inch round, 2 inches deep | 35–40 minutes |
| 8×8-inch square | 30–35 minutes |
| Standard muffin tin | 18–22 minutes |
Keeping Leftovers Fresh
Refrigerate – Wrap any leftover cake tightly or store in an airtight container in the fridge for up to 4 days. The caramel will stay soft even cold.
Reheating – Warm individual slices in the microwave for 20 to 25 seconds, or in a 300°F (150°C) oven for 5 minutes. The heat loosens the caramel again and brings back that just-baked texture.
Frequently Asked Questions
Can I make this cake without rum?
Yes, replace the rum in the caramel with 1 teaspoon of rum extract or 1 teaspoon of vanilla. For the batter, simply use an equal amount of milk or skip it.
What if I only have frozen bananas?
Thaw them completely first and drain any excess liquid before mashing. The cake batter will be slightly wetter, so add an extra tablespoon of flour if it looks too thin.
Why did my caramel turn grainy?
Grainy caramel usually means the sugar crystallized. Use a clean pot, dissolve the sugar fully before boiling, and do not stir once the mixture starts bubbling. A tiny pinch of cream of tartar can also help prevent crystals.
Can I make this a day ahead?
You can bake the cake the morning of, but the caramel is stickiest and most beautiful when you invert and serve it the same day. If you need to get ahead, make the caramel sauce and store it in the fridge; reheat and pour it into the pan just before adding the bananas and batter.
Banana Foster Cake Recipe
Ingredients
Method
- Stir ½ cup butter, dark brown sugar, heavy cream, and pinch salt in a saucepan over medium heat until melted. Stop stirring and bubble 2 minutes. Off heat, stir in 2 tbsp rum. Pour into ungreased 9-inch round pan. Arrange banana slices in a single layer.
- Whisk flour, baking powder, baking soda, and ½ tsp salt. In another bowl, whisk melted butter, granulated sugar, and light brown sugar. Beat in eggs one at a time, then vanilla, mashed banana, sour cream, and remaining 1 tbsp rum. Fold dry into wet just until combined.
- Preheat oven to 350°F (175°C). Spread batter over bananas and bake 30–35 minutes until golden and a toothpick comes out with moist crumbs. Cool in pan on rack for 10 minutes.
- Run a knife around edge, invert onto a plate, and lift off pan. Slice and serve warm.
