If you like bananas, and rum, you will love this roasted banana cake with spiced rum. Roasting the bananas first intensifies their sweetness and flavours creating a rich and sweet cake. And for those of you, who like me, believe a good banana cake is best with a good dose of rum, well I've got you covered.
If you like this idea, you might also want to check out one of my favourite cheesecakes, Banana Caramel Cheesecake, I saute the bananas in this cake too to sweeten them up a little.
Why you should always roast the bananas first
I may never make a banana cake again without roasting the bananas first.
Roasted bananas have a more concentrated banana flavour, but roasting also increases their sugars and sweetness. The result is an intensely sweet and rich banana cake. This cake will please all the banana lovers in your life.
Use fully ripe and spotty bananas for this recipe.
Even though you will be roasting the bananas first and roasting basically makes the softer and sweeter, turning them completely black, you still want to start with fully ripe or even over-ripe bananas. Do you try to use green bananas here.
More bundt cake recipes you might like:
- Lemon Poppy Seed Cake
- Cranberry Orange Bundt Cake
- Chocolate Pecan Bundt Cake
- Double Chocolate Glazed Donut Cake
How to make this cake
First, roast the bananas
Start with fully ripe bananas for this cake. You will need 4 in total. Only 3 of the bananas will be roasted.
Place 3 of the bananas on a rimmed cookie sheet or baking tray and place in a 400-degree oven for 20-25 minutes. The bananas will be completely black when they are done and will have released a little bit of liquid. Set the roasted bananas aside and let them cool a little bit so you can handle them and peel them.
In the meantime reduce the oven temperature to 325 degrees while you make the rest of the cake.
Make the buttermilk - if you need to
See the tip below. If you don't have buttermilk handy, you can make a good substitute by curdling any milk - full fat, part-skim, soy, almond or oat. I used almond milk curdled with a little bit of lemon juice in this recipe.
Mix the dry ingredients
In a small bowl whisk together the flour, baking soda, baking powder and salt. Set aside.
Make the cake batter
Start by peeling all the bananas. Peel the 3 roasted bananas and the 1 unroasted banana and add all the bananas to the bowl of standmixer. Or you could use a large bowl with a handheld mixer if you wanted.
Fit the standmixer with a paddle attachment and beat the bananas on low speed for a minute or two to mash the bananas. Add the buttermilk, or curdled milk if you are using this, see tip below, and mix the buttermilk into the bananas until smooth and creamy.
At this point add the sugar and remaining wet ingredients: eggs, oil, rum and vanilla and mix well but do not whip. You do not want to incorporate too much air into this batter. Remove the bowl from the standmixer.
By hand, fold in the dry ingredients and mix until just combined. Spoon cake batter into the prepared bundt pan. Tap the sides gently to release any air bubbles.
Bake the cake
Bake the cake at 325 degrees for about 40 minutes. A toothpick inserted into the center of the cake will come out clean when the cake is done and the top should be just lightly golden.
Allow the cake to cool for at least 10 minutes before attempting to remove it from the bundt pan. Once the cake is out of the pan, let it cool completely on a cooling rack before glazing.
Make the glaze
The glaze is a simple mixture of icing sugar, milk and rum. I've kept this one simple to let the roasted banana flavour really shine. But feel free to add your favourite glaze-type frosting.
How to substitute buttermilk in recipes
This recipe requires buttermilk, but I don't know about you but I never have buttermilk just hanging around in my kitchen. So I make my own, usually using plant-based milk.
What you will need:
- 1 Tablespoon of lemon juice or vinegar
- Milk or your choice, slightly less than the measure called for in the recipe
Here's how I do it:
You can use any kind of milk, I usually use almond or oat milk without any issues. Of course, you can also use dairy milk, full-fat, 2% of 1% will all work.
Start with an acid. I use lemon juice, white vinegar or apple cider vinegar. I haven't noticed a big difference when using any of these especially when baking a dark cake like this one or maybe muffins. If you are making a white cake you should stick with white vinegar as it is colourless and flavourless.
In your liquid measuring cup add the lemon juice or vinegar first.
Then pour the milk to the desired measurement for the recipe.
I use approximately 1 tablespoon for each 1 cup of milk. In this recipe, which calls for ⅔ cup of buttermilk, I still used 1 tablespoon. If your recipe called for 2 cups of buttermilk or you were going to double a recipe for example, you will need approximately 2 tablespoons of acid.
Wait about 15 minutes for the acid to start to curdle the milk. It will be visibly curdled.
This method works when you need a small amount of buttermilk for a baking recipe. I would not recommend this method in any other application (a beverage recipe for example).
Do not try to use any other type of vinegar, it goes without saying, but red wine or balsamic vinegar are differently flavoured and will impact the colour and flavour of your recipe.
Notes about this recipe
This recipe calls for cake flour. Try your best to get your hands on cake flour. Cake flour produces a lighter crumb which is nice in this cake. But if you must use all-purpose, remove 2 tablespoons per cup of cake flour and replace them with 2 tablespoons for cornstarch.
So in this recipe, which calls for 2-½ cups of cake flour, measure out 2-½ cups of all-purpose flour and remove 5 tablespoons total of all-purpose flour and replace with 5 tablespoons of cornstarch.
I love spiced rum in baking. It's a bit sweeter and has a nice caramel colour and some molasses for flavour. But use your favourite rum. No judgement. If you don't have spiced rum use a good dark rum. Dark rum is better than white rum in this recipe. I used Lamb's Spiced Rum.
This cake uses a full ¼ cup of rum, plus a bit in the glaze, so make sure you use a rum you actually enjoy.
If you don't have rum, another liquer would work.. like a spiced or flavoured whisky for example. But if you don't want to use alcohol, you could substitute apple juice or apple cider. Just be sure to use the same amount of liquid as called for in the cake recipe - a ¼ cup - to keep the liquid volume the same. In the glaze just use more milk instead.
A bundt cake pan
Roasted Banana Bundt Cake with Rum
- 10-cup bundt cake pan prepare with non-stick baking spray or quick release
- 3 very ripe bananas these will be roasted
- 1 very ripe banana mashed, this will be added directly to the cake
- ⅔ cup buttermilk or non-dairy milk soured with lemon or vinegar, see Notes
- 1 cup dark brown sugar firmly packed
- ½ cup canola oil
- ¼ cup dark rum spiced is my favourite
- 2 large eggs
- 1 teaspoon vanilla extract
- 2.5 cups cake and pastry flour
- 1 teaspoon baking soda
- 1 teaspoon baking powder
- ½ teaspoon fine grain sea salt
Vanilla rum glaze
- 1 to 2 cups icing sugar sifted
- 1 tablespoon milk your choice
- 1 tablespoon dark rum spiced is nice
- ½ teaspoon vanilla extract
- Preheat oven to 400 degrees. Place 3 bananas on rimmed cookie sheet and roast at 400 degrees until very black and soft. About 25 minutes. Remove from the oven and allow to cool slightly and peel. Reduce oven temperature to 325 degrees while you prepare the cake.3 very ripe bananas
- Prepare the bundt cake pan with butter and flour or spray with non-stick cooking spray.
- In the bowl of standmixer fitted with the paddle attachement, add the peeled roasted bananas and the 1 remaining banana, run the mixer on low speed to mash the bananas. Add the butter milk and mix until smooth and creamy.1 very ripe banana, ⅔ cup buttermilk
- Add the brown sugar along with the remaining wet ingredients, canola oil, rum, eggs and vanilla and beat at low speed until smooth and creamy. Do not whip. Remove from the standmixer at this point to finish by hand.1 cup dark brown sugar, ½ cup canola oil, ¼ cup dark rum, 2 large eggs, 1 teaspoon vanilla extract
- In medium bowl combine the dry ingredients, cake flour, baking soda, baking powder and salt. Stir with a whisk to combine and set aside.2.5 cups cake and pastry flour, 1 teaspoon baking soda, 1 teaspoon baking powder, ½ teaspoon fine grain sea salt
- Using a rubber spatula or wooden spoon gently fold the dry ingredients into the banana mixture until just combined. Spoon the batter into the prepared bundt ban. Gently tapping the sides to remove any air bubbles.
- Bake at 325 degrees for 40-45 minutes or until a toothpick inserted into the center of the cake comes out clean. Allow the cake the cool at least 10 minutes in the cake pan. At this point you can remove the cake from the pan and place it on a wire rack to fully cool.
Make the vanilla rum glaze
- In a small bowl combine the milk, rum, vanilla and about half a cup of icing sugar. Whisk until smooth and creamy. Add more icing sugar until the glaze is the desired consistancy. The glaze should drizzle and drip as you pour it over the cake, but be thick enough to stick. Add more icing sugar as necesary. Use immediately and drizzle over the cake using a spoon.1 to 2 cups icing sugar, 1 tablespoon milk, 1 tablespoon dark rum, ½ teaspoon vanilla extract
This recipe is slightly adapted from a recipe from Baked From Scratch magazine. As noted above I did not use true buttermilk in my recipe but curdled almond milk (as noted above) in its place with good results. I also choose a simple glaze.