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What I love about This Rhubarb Cake!
- In this flourless, upside-down rhubarb cake, I resisted the temptation to add berries or other fruit, to highlight the rhubarb’s true flavor. The bright liveliness of the rhubarb is front and center, the sourness mellowed slightly with vanilla and butter, while the base of the cake, made entirely of almond meal and no flour, whispers of cardamon. To my palate, the combination delights.
- The cake is totally grain-free.
- If you rather not do it upside-down, you can do it right-side up. See recipe notes.
How to make Rhubarb Cake
Once the rhubarb is just slightly cooked, set it aside, leaving it in the cast-iron skillet. We will bake the cake in this!
In a large bowl, place the egg yolks (the egg whites into a stand mixer) sugar and lemon zest. Mix the yolks with sugar and lemon zest, until creamy, and then gradually mix in the dry ingredients. It will be thick. Set aside.
Whisk the egg whites in a clean stand mixture until stiff peaks form (any oil in the bowl will prevent whites from getting stiff) and then gradually stir in the almond flour batter to the stiff egg whites to create a fluffy batter.
Step three: Pour the cake batter over the rhubarb.
NOTE: Alternatively, you can also pour the batter into a greased 8-10 inch cake pan and top it with the rhubarb ( instead of doing the upsidedown version).
More Rhubarb recipes you may like!
- Rhubarb Muffins
- Rhubarb Crisp
- Baked Salmon with Rhubarb
- Rhubarb Shrub Recipe!
- Rhubarb Tart with Lemon, Cardamom & Vanilla
- Strawberry Rhubarb Cobbler
- Recipes to Celebrate Spring!
Rhubarb Cake
- Prep Time: 20 mins
- Cook Time: 30 mins
- Total Time: 50 mins
- Yield: 8 1x
- Category: Dessert, cake
- Method: baked
- Cuisine: American
- Diet: Gluten Free
Description
This upside-down Rhubarb Cake is baked in a cast iron skillet. It’s gluten-free- and grain free- made with Almond Flour. Deliciously addictive and perfect for Spring.
Ingredients
- 4 cups rhubarb, cut into 1/2 inch cubes (about 1 1/4 lb)
- 1 1/4 cups sugar -divided (or use half brown sugar)
- 4 tablespoons butter
- 1 tablespoon fresh lemon juice
- 2 teaspoons vanilla extract
- pinch salt
- 4 eggs, separated into 4 egg yolks and 4 egg whites, room temperature
- zest from one lemon
- 1/4–1/2 teaspoon cardamon
- 1 1/2 cups finely ground almond flour or meal
- 1 teaspoon baking powder
- 1 teaspoon white or cider vinegar
- Powdered sugar for sprinkling
Instructions
- Pre heat oven to 375 F
- Over medium heat, melt butter into a well-seasoned, 9-10 inch cast iron skillet, and brush the sides with it. Add rhubarb, ¾ cups sugar, lemon juice, 2 tsp vanilla and pinch salt and stir for 2 minutes, just until combined and sugar has dissolved. Turn the heat off. Do not continue to cook rhubarb.
- In a medium bowl, whisk egg yolks with lemon zest, cardamon and ¼ cup sugar, until creamy and sugar has dissolved. Set aside. Add the baking powder, and salt, and stir. Whisk in the almond flour a little at a time.
- You will have a very thick heavy batter at this point.
- In a stand mixer, with the whisk attachment, whip egg whites on medium-high speed, and once you see bubbles, add a pinch of salt and tsp vinegar . Whisk until egg whites have formed soft peaks, then add the remaining ¼ C sugar a little at a time whipping until medium-stiff peaks form. Turn speed to down to medium-low and begin spooning in the thick egg yolk batter, a heaping spoonful at a time, into the egg whites, until it is all combined, scraping down sides as necessary.
- Pour batter over rhubarb in the cast iron skillet and place in a preheated oven, for 30 minutes. While baking, make sure to have ready, what you plan to flip the cake on to. At 30 minutes, check for doneness by inserting a toothpick or skewer into the middle of the cake. If it comes out clean, it is done. If not, bake 5 minutes longer, check again. Pull from the oven, and if making in a skillet, immediately place a cake platter or cake stand over the skillet, and invert, gently tapping the bottom of the skillet so it releases.
- Serve with vanilla ice cream or on its own. The cake is especially good the next day.
Notes
I use a 9-inch cast iron skillet for this recipe! I’ve tried it with a spring form pan- and no leaks- but readers are having issues with leaks. So line with parchment or use a cast iron skillet. 😉
You can also bake in a greased cake pan, and pour the rhubarb over top before baking.
Nutrition
- Serving Size:
- Calories: 346
- Sugar: 32.9 g
- Sodium: 331 mg
- Fat: 12 g
- Saturated Fat: 4.4 g
- Carbohydrates: 39 g
- Fiber: 2 g
- Protein: 6.8 g
- Cholesterol: 108.3 mg
Keywords: rhubarb cake, rhubarb cake recipe, gluten free rhubarb cake, upside down rhubarb cake, rhubarb recipes, rhubarb cake recipes, gluten free recipes
Recipe list states baking powder but written recipe says baking soda?? Which one is it??
Sorry Sara! Baking powder. Thanks and updated the instructions. 🙂
question – do you need to refrigerate the cake after cooled for next day enjoyment?
You can Jessica, but I usually just leave it out on the counter, lightly covered- it is fine for a few days.
Yummy! It came right out of my cast iron pan with no problem. Almond flour cakes are sometimes delicate, and this one was. It’s not pretty enough for company, but for my husband and I, it’s perfect! Maybe a smaller cast iron would have worked better. Yours looks beautiful and mine, not so much. My rhubarb cooked up brown-ish as well, and your’s is red. But it tastes divine,and isn’t that all that counts
★★★★
So happy you enjoyed this Alene. For the photos, I purposely sought out the reddest rhubarb stalks I could find.
Absolutely delicious flavor, but the rhubarb part was way too juicy, and it came out like oatmeal with a rhubarb sauce. I also used a sugar alternative (monk fruit) as I am diabetic. I would try making this again, but I think I would add some tapioca flour to the rhubarb ingredients to thicken it. And I would probably bake it a bit longer next time!
I really think it is the sugar substitute making it more juicy. I’m not positive, but it’s my best guess. 😉
Loved this recipe! the flavor was great and my gluten-free friends enjoyed it. Can this recipe be modified to us standard flour? At times I run out of almond flour and my immediate family doesnt have gluten issues.
You know, great question Ann and I’m not sure! I think it should work?? But not positive. 😉
Hello I am not going to rate the recipe, because I believe it failed due to my substitution of Swerve for the sugar. My daughter cannot have sugar while she is on her current diet. I used the exact amount (as the Swerve package states that substitution for sugar is 1:1) and my fresh rhubarb seemed to release A LOT of liquid (much more than your photo), however I didn’t drain it, as I would have removed the Swerve. Not sure if the excess liquid was due to my extra juicy rhubarb, freshly picked from my garden, or using the Swerve. The cake portion rose and baked beautifully, but it soaked up all the liquid. Although the cake surprisingly maintained it’s structure, it was very soggy – like a sweet, wet sponge! So perhaps I will try again subbing the sugar with honey (as she can have a little of that).
Oh shoot Robin! Yes not sure about the Swerve- I have never used it, so not sure how it works in recipes? I use fresh rhubarb here as well-it does get juicy, but not overly, so don’t think it was that? Appreciate you sharing this, maybe useful to someone else out there!
A hit! Could not find ruhbarb, used fresh picked blueberries. It wAs a treat!!!
★★★★★
Nice Katey! Yum fresh blueberries, that sounds amazing.
Deeelucious light and tasty. I baked the rhubarb in a round metal non stick cake pan with the butter in the oven until it bubbled and it worked perfectly.
★★★★★
Wonderful to hear Diane!
I wish that I had printed this recipe before the changes were made to it. I make it in a regular cake pan, without the fruit, topping it with a maple glaze instead.
★★★★
Hi Beth, the recipe itself has not changed- only the pan. It use to have a spring form pan option, but people were having issues with it leaking. A cake pan should work great!