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Separate the yolks from the whites. Mix the yolks with sugar and lemon zest, and combine with dry ingredients. Whip the whites, and then combine all to create a batter.

Pour the almond flour batter over the rhubarb.





Upside Down Rhubarb Cake (Gluten-free)
- Prep Time: 20 mins
- Cook Time: 30 mins
- Total Time: 50 mins
- Yield: 8 1x
- Category: Dessert, gluten-free
- Method: baked
- Cuisine: American
- Diet: Gluten Free
Description
Upside Down Rhubarb Cake that is gluten free- made with Almond Flour. Deliciously addictive, perfect for Spring. Made in a cast-iron skillet.
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 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 C sugar, lemon juice, 2tsp vanilla and pinch salt and stir for 2 minutes, just until combined and sugar has dissolved. Turn heat off. Do not continue to cook rhubarb.
- In a medium bowl, whisk egg yolks with lemon zest, cardamon and ¼ C sugar, until creamy and sugar has dissolved. Set aside. In a small bowl, whisk almond flour, pinch salt, and baking powder until combined.
- Add flour mixture to egg mixture and stir to incorporate. You will have a very thick heavy batter at this point.
- In a stand mixer, whip egg whites on medium high speed, and once you see bubbles, add a pinch of salt and tsp vinegar . Whip until egg whites have formed soft peaks, then add 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 flour – egg yolk batter, a heaping spoonful at a time, into the egg whites, until it is all combined, scraping downs 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 personally use a 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 I recommend a cast iron skillet. 😉
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: gluten free rhubarb cake, upside down rhubarb cake, rhubarb recipes, rhubarb cake recipes, gluten free recipes
HOW MANY CARBS IN ONE SLICE ?
I just added the nutrition label Richard. 39 carbs in 1 serving ( serves 8).
This was fantastic! I made it in a 8 x 8 sq cast iron pan and it came out perfect. I’m going to try it with other fruits and monk fruit. Thanks for the recipe.
★★★★★
Great to hear Peggy!
This recipe is amazing. I’ll be adding it to my list of favorites because it never disappoints and the flavors are perfect for summer. The cake is moist and the hint of lemon is sooooo good and really compliments the rhubarb. Bake time was perfect for my 10 inch skillet.
★★★★★
Awesome Bianca! Glad this worked for you!
Can this be frozen?
I haven’t tried freeing this, but I don’t see why not? Maybe only hesitation would be discoloration of the rhubarb?
Can you make in a glass 9 x 13 pan?
Hey Peggy- good question and I’m not sure! I’ve only done it in a cast-iron and cheese cake pan. In theory it seems like it should work??
Can I substitute maple syrup or coconut sugar?
Hi Karen- I have not tried substituting here so not positive how this would affect the texture of the cake. Truthfully, I am hesitant to change anything as this one can be a bit tricky (the flipping) on the first go around. I do think coconut sugar would be better than maple though.
This is my new favourite cake recipe! I have 2 rhubarb plants in my garden so it’s perfect. I use a springform pan as I don’t have an appropriate skillet. You just have to line with parchment paper without cutting a circle so there is nowhere to leak. There are a few crease marks from the paper on the cooked batter but it’s barely noticeable. I also added a few drops of pink food colouring on the rhubarb mix for a more vivid colour effect! Thank you!
This was absolutely fantastic! It turned out great in our favorite cast iron skillet, and I used leftover rhubarb from your shrub recipe (yum!) and added some fresh cherries that needed to be used up. I reduced the amount of sugar by 1/3 cup as the rhubarb had already been soaked in sugar, and since I like desserts with less sugar. I cooked it an extra five minutes, but I had no problem with too much liquid. I will make it again very soon, as my husband and two boys have just devoured it!
★★★★★
Yay!!! Thanks so much, and glad it turned out for you Amy! 🙌
So disappointed. What an expensive mess. Followed the recipe to the letter and all the lovely sugary liquid leaked out. Not sure how you managed to avoid leaks in a springform pan as several other comments had the same problem. Now I have an enormous mess in my oven and a slightly sour cake with an unpleasantly eggy texture and taste. First and last recipe I’ve tried from this site.
★
Hi there- sorry you had a mess. I understand the frustration. I’m not sure if you had an older version of this recipe printed? but I updated recipe notes, stating not to use a springform pan (for this reason) but rather a cast-iron skillet for best results.
I use a springform pan lined with a single piece of parchment paper all over (it creases a bit on the inside) but it works perfectly and never leaks as I don’t own a skillet.
★★★★★
Thanks Amanda! Apreciate this!
I made this and it was excellent!! Only change I made was I used erythrytol instead of sugar and it turned out great. Will definitely make again.
★★★★★
Just realized I had already posted s review. My bad! Sorry
Hi, made this tonight for second time, but using frozen rhubarb. Drained out most of liquid, and then when cake was done….a tad early though….say 25 minutes? I poured the liquid into a pan, added cornstarch and then once thickened poured it over inverted cake. YUM!!!! Thinking this recipe will be good with other fruits too! Thank you!
This recipe was an expensive fiasco it did not set up as promised and turned into way too much liquid and should’ve had some thing like corn starch or tapioca to absorb all that liquid. I ended up cooking it an extra 20 minutes after I had already turned it into a serving dish and noticed a wet mess in the middle of a puddle of rhubarb juice. I put the whole mess into a 9 x 13 oblong pan and cooked it for another 20 minutes and proBanks will refrigerate it to see if it held prior to serving or making into a cobbler with some GF granola to absorb more liquid
Sorry, it didn’t work for you. Not sure what happened…
Made this last night and it got rave reviews! So tasty. After reading some reviews I did drain a bit of the liquid from the fry pan before pouring in the batter. Baked as directed and it came out beautifully. Thank you for this recipe. I’ve been searching for a great dessert with no sugar or wheat flour. This fit the bill.
★★★★★
Awesome Monica!
Delicious!
★★★★★
Well that fills the rhubarb craving!
I a cast iron pan and also had juices that ran onto my serving plate. I used Monk Fruit Erythritol (low carb alternative) in place of the sugar, so it may have responded differently than sugar. Next time (and there will be a next time!), I’ll just add some corn starch to the rhubarb layer.
I also lightened the egg/flour mixture with some of the beaten egg whites so they would incorporate easier…and it seemed to work well. The cake has great texture and favour!
★★★★
I make this cake 2-3 times every spring (yes, for a few years now), sometimes just with rhubarb (like last night) and other times with berries too. And every time, it just sits in the cast iron pan and gets devoured straight from the pan. LOVE LOVE LOVE! Thank you for this gem!
★★★★★
Awwwww thanks Jessica! I’m so glad you like it! I like it too! 😉
Love this cake. Favorite of the season! I add a little almond extract to the dough. Fantastic.
★★★★★
Those are rhubarb STALKS, not stocks.
haha. Yup. 🙂 thanks.
I’m glad to have a new option for rhubarb. I made this exactly as written…it is a bit of a kitchen-destroyer with all the bowls required, but I would say it’s worth it! Served it to our visiting international students who had never seen or tasted rhubarb…everyone loved it!
★★★★★
Awesome! Glad you liked it!
Okay, so why did my rhubarb leak liquid everywhere? I used a spring-form pan, lined and buttered. I followed the recipe to the letter. Result was liquid from teh rhubarb mixture all over …. I am afraid to cut into it. What did I do wrong?
It does smell delicious.
Thanks.
★★★★
How did it turn out?
Beautiful recipe. Trying it with fresh plums right now.
★★★★★
Made this today 5/7/2019. Is there a missing ingredient like cornstarch to thicken the rhubarb sauce? It ran all over my counter and burned the pan under the springform pan???
Oh No Jill! I didn’t use cornstarch but I think I see the problem.First, can you confirm if you used parchment and had the lid inserted with the bumpy side up? Otherwise, directions are not clear. I Will update. If using a spring form pan, let this set 20 minutes before flipping. If using cast iron, flip right away.
I made this last week with rhubarb from the freezer, and it was delicious. However, the egg yolk/flour mixture was really stiff and heavy, causing the whipped egg whites to fall. Trying it again for Easter dinner (we really loved the flavor) and using another egg and less flour. Will let you know how that works. (PS. I baked it in my skillet, which was another lovely touch to the recipe.)
★★★★
I have been looking for ways to use the gallons of rhubarb I have frozen from 2018. I made this tonight. I discovered that my cast iron pans were rusty so I just used an 8”x8” pan. It just fit in the pan and did not run over the side. I also realized half way in that I didn’t have a lemon!! So I used orange juice and some lime and orange zest.
As you may know, baking with frozen rhubarb can be difficult. I drained the rhubarb thoroughly and added more sugar and let it cook at bit longer. It still gave so much juice. But it turned out great. Came right out of the pan. I’m going to share this with my family and friends.
Thank you!!
★★★★★
For a rhubarb lover – this is delicious. Like someone mentioned – you use a lot of bowls! I followed the directions exactly. When I took the cast iron came out of the oven, it basically flew onto the serving dish – juice et al. I definitely think a modification with cornstarch or tapioca would be helpful. The flavor was exceptional! I would make this again and serve it right from the cast iron. The juice is great on vanilla ice cream:)
★★★★★