Gluten Free Upside Down Rhubarb Cake makes the most of rhubarb’s short, beautiful season, tucking it into a perfectly tart-sweet cake.
Quick! It’s rhubarb season just for a bit longer. Go get yourself some of this unique vegetable and make a gorgeous pink upside down rhubarb cake. A simple and familiar blend of gluten-free flours and maple sugar and honey to sweeten makes the absolute most of rhubarb’s fleeting season.
Today’s recipe is an adaption of a rhubarb-spelt cake I developed a few years ago when I was thrilled to be able to access rhubarb again at the grocery store in Sydney. The oat and sorghum flours in this combination mimic the whole grain sweetness and tender crumb of the spelt flour, while sweet rice flour acts as a lovely binder that is balanced by a bit of tapioca flour to keep things light. Honey sweetens the rhubarb, which of course is quite sour on its own, and my beloved maple sugar gives the cake a beautiful caramelized, not-too-sweet note.
I’ll admit it — this is one of my favorite recipes, and I’m delighted that I can now make it gluten-free. Hope you’re able to try this one; it’s a winner.
Original recipe is here.
Need substitutions? Swap sorghum flour for the oat flour, almond flour for the sweet rice flour, millet flour for the sorghum flour, and arrowroot for the tapioca. Swap white sugar for the maple sugar. Try two flax eggs in place of the eggs and your favorite non-dairy butter and milk to make dairy-free.
Gluten-Free Upside Down Rhubarb Cake
- ½ cup honey
- 4 tbsp unsalted butter
- 1 organic lemon, zested
- ¼ tsp fine sea salt
- 1 lb rhubarb, washed, trimmed, and sliced into long 1/4-inch pieces (the pieces should be about the length of your cake pan)
- ⅓ cup + 1 tbsp /70 g sweet white rice flour
- ¼ cup + 2 tsp/50 g sorghum flour
- ¼ + 1 tbsp 45 g gluten-free oat flour
- ¼ cup + 1 tbsp/45 g tapioca flour
- 1 ½ tsp baking powder
- ¼ tsp fine sea salt
- ½ cup unsalted butter, at warm room temperature
- 1 cup maple sugar or sugar
- 1 large eggs
- ½ cup + 1 tbsp whole milk
- 1 tsp pure vanilla extract
- In a large cast iron pan or skillet, melt the honey and butter over low heat. Stir in the lemon zest and salt. Spread the rhubarb out evenly and cook until slightly softened and releasing its juices, about 5 minutes. Remove from heat.
- Heat oven to 350° F. Butter an 8 or 9-inch round cake pan and line with a circle of parchment. Pour in the cooked rhubarb and set aside.
- In a small bowl, whisk together the flours, baking powder and salt.
- In a large bowl and using an electric mixer on medium speed, cream the butter, scraping down the sides of the bowl as necessary, until the butter is lighter in color, about 45 seconds. Then add the maple sugar in a steady stream and scrape down the bowl again. Continue to mix on medium speed until the mixture is very light in color and texture, about 4 to 5 minutes.
- In a small bowl whisk the eggs. Slowly pour in the eggs a little at a time, and beat very well for about 2 minutes.
- Combine the vanilla and milk in a small bowl or measuring cup.
- With the mixer on low, add the flour mixture in two doses, alternating with the milk. Scrape down the sides of the bowl in between additions.
- Pour the batter on top of the rhubarb, smoothing gently. Place cake in the oven and bake for 35-45 minutes, or until a toothpick inserted in the center comes out clean. Check after 35 minutes; you want the cake to lightly spring back in the center when pressed.
- Remove cake from the oven and set on a rack to cool for 10 minutes. Run a butter knife around the side of the pan to loosen the cake, then turn out onto the rack to finish cooling completely.
- Cake will keep, well wrapped in the fridge, for 5 days.