Gluten-Free Banana Upside-Down Cake

Baked with a buttery brown sugar layer and bananas on the bottom, this gluten-free banana upside-down cake flips over to reveal a seductively caramelized banana topping that's gooey and oh-so-sticky.

The sticky topping gives way to a floofy tender cinnamon teff flour cake that exudes warm nutty and toffee notes. This cake is the just-right transition into fall, but with bananas available all year round, it's also the perfect anytime anywhere cake. This cake makes me swoon.

What is an upside-down cake?

An upside-down cake is baked with fruit and sugar on the bottom and cake batter on the top. As it bakes, the sugars caramelize with the fruit while the cake bakes above. Shortly after it comes out of the oven, the cake is flipped to reveal the fruit on top and the juices and caramelized sugars begin to seep into the cake below. 

The benefit of an upside-down cake is that the fruit sits right on top as a gooey sticky topping. Unlike a cake with fruit baked on top, an upside-down cake does not run the risk of the juicy fruit causing an underbaked or too moist cake.

Added bonus: upside-down cakes are beautiful showstoppers!

Gluten-Free Cinnamon Butter Cake

While the bananas are here for the sticky topping, the cake underneath contains no bananas. Rather it's a simple gluten-free cinnamon butter cake that's both fluffy and incredibly moist. The warm spices are a perfect complement to the caramelized banana topping, giving depth of flavor. 

The cake uses teff flour as the flavor driver, with subtle toffee notes that are both nutty and sweet.

Gluten-Free Flours and Substitutions

For gluten-free cake, I prefer to use a homemade blend of flours specific to the cake I'm making - this allows me to pair flours for flavor and texture, while using whole grain flours. For all my homemade flour blends, I recommend Bob's Red Mill brand flours, which are high-quality and have a consistent grind.

For this gluten-free banana upside-down cake, I use a blend of sorghum flour, sweet rice flour, tapioca flour, and teff flour. Below I describe each flour and also recommend a few substitutions if you can't find that particular flour. A note about substitutions: I have not tested this particular cake with most of these substitutions (unless noted), so your results and baking time may vary slightly. These are, however, my recommendations based on lots of experience with gluten-free cake baking and I'm confident they'll work.

SORGHUM FLOUR

Sorghum flour is a wholesome whole grain flour. With slightly sweet notes, sorghum flour adds flavor depth and helps creates a very moist crumb. 

• Sub in by weight: you can substitute gluten-free oat flour or Bob's Red Mill 1-to-1 all-purpose gluten-free flour blend. 

SWEET RICE FLOUR

Made from sticky rice, sweet rice flour is distinctively different than white rice or brown rice flour, and despite its name, it's not sweet. Sweet rice flour is the same flour used to make mochi, and as such, its stickiness helps to bind the cake together, creating chewiness like a classic cake recipe. 

• I don't recommend substituting the sweet rice flour as I find it's essential to the recipe. However, if you're unable to find it, you can replace it with Bob's Red Mill 1-to-1 all-purpose gluten-free flour blend or additional tapioca flour by weight.

TAPIOCA FLOUR/STARCH

Tapioca flour adds chewiness and helps mimic the fluffiness of a classic cake. It adds just a bit more softness and loftiness to the crumb. 

• Sub in by weight: If you need to sub it out, I would recommend arrowroot starch, potato starch, Bob's Red Mill 1-to-1 all-purpose gluten-free flour blend, or using equal parts more sorghum flour and sweet rice flour, by weight.

TEFF FLOUR

Teff flour is such a warm flavorful flour that's the perfect pairing for a cinnamon cake. In this cake, teff flour is the flavor driver. You don't need a lot to get the flavor benefits. As a powdery fine flour, it bakes up soft and fluffy with rich toffee notes that accentuate the caramelized banana topping. 

• Sub in by weight: You can sub in 15g more each of sorghum flour, sweet rice flour, and tapioca flour, but your cake will turn out lighter in color and less flavorful. You could also sub in chestnut flour, millet flour, or Bob's Red Mill all-purpose gluten-free flour.

XANTHAN GUM

In this cake, the xanthan gum is not optional. Without it, the batter is thin and seeps up under the bananas and the cake bakes up dense.

If you’re just starting out with gluten-free baking, I understand that the hefty price tag on xanthan gum might steer folks away from using their own homemade flour blends that call for it. If you're in that camp, just know it lasts for a long time! I keep it in my fridge and a bag lasts me almost 2 years, so if you plan on getting more serious about gluten-free baking, a little goes a long way. Each recipe typically only calls for ½-1 teaspoon.

ALL-PURPOSE BLEND

If you'd prefer to use a pre-made blend, you can sub out all the flours by weight (244g) along with the xanthan gum with Bob's Red Mill 1-to-1 all-purpose gluten-free flour blend.

Banana Upside-Down Cake Tips

• Line the bottom of the pan with parchment paper to help remove the cake and fruit easily from the pan
• Use ripe but firm bananas. If the bananas are too ripe to halve, then you'll have trouble arranging the bananas, but you do want to use ripe bananas as the more ripe they are, the sweeter and more flavorful the bananas. I do not recommend frozen bananas as they do not hold their shape when defrosted.
• Flip shortly after baking. Letting the cake cool too long in the pan will result in the caramel firming up and the fruit will stick to the bottom of the pan.
• Serve warm or room temperature. Top with whipped cream or vanilla ice cream if you're feeling fancy.

Can I use a cast-iron skillet?

Yes! If using a cast-iron skillet, you can melt the sugar right into the cast-iron skillet then place the bananas on top followed by the cake batter. Your cake may take less time to bake given the dark cast-iron skillet, so check for doneness about 5 minutes early. 

How to flip an upside-down cake?

The timing of flipping an upside-down cake is essential. Cool the cake only 5-10 minutes after it comes out of the oven before flipping. Cooling longer than 10 minutes will result in the caramel beginning to firm up and the fruit will stick to the bottom.

Start by running a knife around the outside of the cake. Place a wire rack over the top of the cake pan with a plate or baking sheet nearby to catch drips. Using oven mitts to hold the cake pan and the wire rack together, flip the cake over onto the plate/baking sheet. Carefully lift the cake pan to release the cake. 

Spoon any caramel left in the pan over the top, and if any banana bits remain stuck to the pan, carefully arrange them back on the cake. Let cool for at least 30 minutes before slicing and serving.

How do you store a banana upside-down cake?

Store leftover banana upside-down cake covered at room temperature for 24 hours or in an airtight container in the fridge for up to 3 days. Cool to room temperature or microwave for 15-20 seconds before serving. 

After cooling completely, store the whole cake or individual slices wrapped tightly in the freezer for up to 3 months. Defrost to room temperature before serving. 

More Gluten-Free Banana Recipes

• Gluten-Free Banana Bread
• Gluten-Free Tahini Banana Muffins
• Chocolate Banana Tahini Popsicles
• Healthy Spiced Banana Date Cake
• Coconut Chocolate Chunk Banana Macadamia Nut Muffins