This Rhubarb Cake is gluten-free, grain-free, made with Almond Flour. Deliciously addictive, perfect for Spring! Make it upside-down or right-side up, your choice!
It is the giving of attention – that keeps us awake.
Mark Nepo
I love this recipe for Rhubarb Cake! In Spring, one of the first things to poke their arms out of the ground is the rosy-colored stalks of rhubarb. They surprisingly have many uses in the kitchen- but what they are known for most is pie. Rhubarb is also called the “pie plant”- and paired with strawberries, berries, or apples, rhubarb is often thought of as a fruit – but in actuality, rhubarb is a vegetable in the same family as sorrel. It actually tastes sour, alot like sorrel.
Rhubarb’s flavor and aroma hint of tart apples, berries, and more subtler notes of water and fresh green grass.
Tip: Always remember Rhubarb “greens” are toxic, always use the stems only, never the greens.
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
It starts with four cups of fresh rhubarb, cut into ½ inch cubes.
TIP: Choose the reddest rhubarb pieces you can find for the best presentation!
Step One: In a heavy bottom skillet, melt butter, and add rhubarb, sugar, lemon juice and vanilla. Stir until combined and sugar has dissolved, but do not cook the rhubarb through, it will cook in the oven. Also, this is the only “fat” in the cake, so I don’t recommend cutting back, the butter will seep into the cake and it is tasty. 🙂
Once the rhubarb is cooked, set it aside, leaving it in the cast-iron skillet. We will bake the cake in this!
Tip: If your rhubarb is not very colorful ( your stems are green) you can always add a some berries to give this some color.
Step Two: Make the cake batter. In a large bowl, whisk the eggs, olive oil, honey or maple and vanilla. Add the lemon juice and lemon zest, cardamom and salt. Ready your baking pan.
Whisk in the baking soda until fully incorporated, then whisk in the almond flour.
Step three: Pour the cake batter over the rhubarb.
NOTE: Alternatively, you can also pour the batter into a greased 9-10 inch cake pan and top it with the rhubarb (instead of doing the upsidedown version).
Step four: Bake in a 350 F oven on the middle or lower rack, for 30-45 minutes or until puffed in the center and golden, and a toothpick comes out clean. Pull it out.
Step five: Let is stand 5 minutes, run and knife along the edges and invert onto a platter. Sprinkle with powdered sugar. Let it stand 10-15 minutes before cutting to let it set.
Serve with vanilla ice cream or whipped cream.
Enjoy the cake! You can leave it out on the counter, covered for 4 days, though I doubt it will last that long. 😉
xoxo
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: 40 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
Units
Scale
Rhubarb Topping
- 4 cups rhubarb, cut into 1/2 inch cubes (try to use red parts for the prettiest presentation)
- 3/4 cup sugar
- 3 tablespoons butter
- 1 teaspoon fresh lemon juice
- 1 teaspoon vanilla
- pinch salt
Almond Flour Cake
- 4 eggs
- 1/4 cup olive oil
- 3/4 cup real maple syrup, agave syrup or honey
- zest from one lemon
- 1/4 cup lemon juice
- 2 teaspoons vanilla
- 1/2 teaspoon cardamon
- pinch salt
- 1 teaspoon baking soda
- 3 cups finely ground almond flour (360 grams, or 12.5 ounces)
Instructions
- Preheat oven to 350 F
- Over medium heat, melt butter into a well-seasoned, 9-10 inch cast iron skillet, and brush the sides with it. Add rhubarb, 1/2 cup sugar, lemon juice, vanilla and pinch salt and simmer for 2-3 minutes, just until combined and sugar has dissolved. Turn the heat off. Do not cook rhubarb all the way through.
- In a medium bowl, whisk the eggs with olive oil and honey. Add the lemon juice, lemon zest, vanilla, and cardamon, and salt.
- Whisk in the baking soda and the almond flour a little at a time. You will have a very sticky batter at this point.
- Make sure the edges of the skillet are greased with butter. Pour batter over rhubarb in the cast iron skillet and place in a preheated oven, middle rack for 30-45 minutes.
- While baking, make sure to have ready what you plan to flip the cake onto. 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, continue baking longer, and check again every 5-7 minutes. Pull from the oven, let sit 5 minutes, run a sharp knife around the edges, then 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 whipped cream.
Notes
I use a 10-inch cast iron skillet for this recipe! I’ve tried it with a 9-inch spring form pan- and no leaks- but some readers have had issues with leaks. So if using a spring form pan, line the bottom with parchment and bake over a sheet pan.
Feel free to add almond extract, more almond flavor.
Nutrition
- Serving Size:
- Calories: 350
- Sugar: 22.4 g
- Sodium: 220.7 mg
- Fat: 15.2 g
- Saturated Fat: 3.6 g
- Carbohydrates: 28.5 g
- Fiber: 1.8 g
- Protein: 6.5 g
- Cholesterol: 72.2 mg
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! 🙌
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:)