This gluten free banana cake with cinnamon buttercream is TO DIE FOR!! The cake is so incredibly light and fluffy, you’d never know it’s gluten free!
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Once bananas get just slightly soft, with any brown spots at all, I won’t eat them. I just don’t like the texture at that point–mushy. Mushy bananas in baking is a good thing, however.
Baking the Gluten Free Banana Cake
This cake is so simple to throw together. With fresh overripe bananas usually offering a more dense texture, it’s surprisingly light and airy! The method of alternating wet and dry ingredients helps to keep the cake so light, but also very moist.
For this cake, I added cornstarch for the effect of a gluten free cake flour. I simply swapped a little of the flour with cornstarch. This also helps to create that soft and tender crumb.
Making the Frosting
This is a simple American buttercream using just four ingredients: butter, powdered sugar, cinnamon, and vanilla. The secret to getting the fluffiest American buttercream is to first cream the butter. Then slowly add the powdered sugar and beat for several minutes (at least 5-7) until light and fluffy. The additional beating time really makes a HUGE difference in the final texture. It becomes a fluffy, whipped frosting that is absolutely perfect with this banana cake!
Frosting the Cake
I always think cakes with a lot of height look so much more elegant. Sure, you could just bake this into two layers (increasing the baking time) but three layers means you get a nice and tall cake with the perfect cake to frosting ratio, and who doesn’t love that?
I did a simple design on this cake using a frosting comb. It looks just like a little comb with teeth, only it’s for cakes and not hair 😉 You can find them just about anywhere, even at a grocery store, or a craft store that sells cake decorating stuff. You can always order them online.
A turntable (for cake decorating) makes it easier, but I actually did this one without my turntable. I put the cake on the platter, held the comb at a 90-degree angle against the cake, and slowly turned the platter. Then I added rosettes on the top border with a pastry bag and large open star tip. It’s so simple, but looks pretty and rustic.
Next time you have overripe bananas lying around, make this cake and save the smoothie for another day. You’re sure to go bananas 🙂
Gluten Free Banana Cake with Cinnamon Buttercream
For the banana cake:
- 3 cups (375 g) Kim's gluten free flour blend (or your favorite blend containing xanthan gum)
- 4½ tbsp cornstarch
- 1¾ tsp baking powder
- 1 tsp baking soda
- ½ tsp salt
- 1 cup (240ml) buttermilk, preferably whole fat
- 1 tbsp vanilla
- ½ cup plus 6 tbsp (200 g) butter, at room temperature
- 1½ cups (300 g) granulated sugar
- 3 large eggs
- 1½ cups (360g) mashed ripe bananas (about 3-4 bananas)
For the cinnamon buttercream:
- 3 cups (680 g) butter, at room temperature
- 6 cups (680 g) powdered sugar
- 2 tsp vanilla
- 1 tbsp ground cinnamon
For the cake:
- Preheat the oven to 350° F. Line three 8-inch cake pans with parchment and spray with non-stick spray.
- In a large bowl, whisk together the gluten free flour, cornstarch, baking powder, baking soda, and salt. Set aside.
- Combing the buttermilk and vanilla in a large measuring cup with a spout. Set aside.
- Cream the butter and sugar in the bowl of a stand mixer fitted with the paddle attachment on medium high speed until the mixture is smooth and creamy, 3-4 minutes. Add the eggs, one at a time, mixing well after each, and scraping the bowl afterwards.
- Add the mashed bananas and mix on low speed just until combined.
- Add the dry ingredients in three parts, alternating with the wet ingredients in two parts, beginning and ending with the dry. Keep the mixer at the lowest speed, and mix with each addition just until the ingredients are combined. When everything has been added, scrape the bowl and mix on medium-low until smooth, about 30 seconds.
- Let the batter rest for 15 minutes. Stir gently before using.
- Fill each cake pan with ⅓ each of the batter and smooth the tops with an offset spatula. Bake for about 25-28 minutes, or until a toothpick inserted in the center comes out clean.
- Let the cakes cool in the pans for about 15 minutes before removing to a rack to cool completely.
For the buttercream:
- In a stand mixer fitted with the paddle attachment, cream the butter. Start with the mixer on low and then gradually increase the speed. The butter should be lighter in color. This should take about one minute. Scrape the bowl.
- Add the sugar slowly and mix on low until all the sugar is combined. When the sugar has been fully incorporated, add the vanilla and cinnamon and mix to combine. Increase the speed to medium high and beat until light and fluffy. This should take at least 5 minutes. You will notice the change in texture and the color will also lighten. Scrape the bowl and beater and mix briefly (about 30 seconds) just to combine once again.
- Frost cakes as desired.