Gluten free rhubarb upside down cake makes the most of rhubarb's short season. A tender, buttery cake is topped with sweet-tart pink rhubarb that's been cooked in honey until meltingly soft.

During rhubarb's fleeting season, you'll want to make all the things, like gluten free rhubarb scones, gluten free rhubarb muffins, and gluten free rhubarb bread! Grab as much of this unique vegetable as you can, then set aside some time to make a gorgeous, pastel pink, gluten free rhubarb upside down cake.
This recipe is a gluten free variation of my rhubarb upside-down cake (developed when we lived in Sydney and was thrilled to be able to access rhubarb again at the grocery store). Silky-soft, honey-sweetened stalks of rhubarb drape over a tender and buttery gluten-free cake. It's delicious warm, wonderful cold, and I love it for dessert or as a mid-morning nibble. You just can't go wrong.
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Make this GF Rhubarb Cake!
I dearly love rhubarb—in May and June, I'm stockpiling as much of it as I can find and tucking it into strawberry rhubarb jam or making my husband a rhubarb gin and tonic. Perhaps because the season is all too brief, rhubarb holds a special place in my heart. And, I love how versatile it is! Rhubarb compote, rhubarb cream cake, rhubarb galette, rhubarb crumble ... it's safe to say I can't get enough. This cake is a highlight of spring, with a simple yet amazingly tender gluten-free cake topped with lightly sautéed rhubarb for a beautiful and delicious presentation. I really want you to make this one! It's:
- Easy and reliable. A classic gluten free butter cake forms the base of this pretty-in-pink treat, and if you've made my recipe before, you know how absolutely simple it is to make.
- So rhubarby. What is it about rhubarb that makes it stand out? It has such a unique flavor that's complemented so well by the honey's natural sweetness. But the honey doesn't overpower the rhubarb; you'll get big, gorgeous rhubarb flavor in every bite.
- Nicely balanced. A hint of tartness remains despite the honey, which is contrasted by the just-sweet-enough cake.
Ingredients Needed
Make sure to scroll down to my recipe card at the bottom of this post for the full ingredient amounts and instructions!
- Honey - If you wish, try maple syrup in place of the honey. Light brown sugar or a mix of honey and sugar will also work.
- Salt - Fine sea salt or table salt is best.
- Rhubarb - Choose firm stalks of rhubarb with no soft, brown spots; the rhubarb should not be limp. It's OK if it's not pink—rhubarb does not always show up as pink when it's ripe. If you prefer a deeper pink hue on the cake, make sure to choose stalks that are pinkish red rather than green.
- Gluten free flour - My homemade gluten free flour blend is perfect in this recipe! You can use a gluten-free blend of your choice, but note that my blend, which I used to develop this recipe, does not contain xanthan gum.
- Baking powder - Always make sure to check the expiration date on baking powder before using it to make sure the cake rises properly!
- Butter - I used unsalted butter, softened to room temperature. You will need butter for the cake and for the topping.
- Sugar - I used granulated sugar. Light brown sugar or maple sugar will also work.
- Egg - A large egg at room temperature.
- Milk - I prefer whole milk, and 2% milk also works.
- Vanilla - Use pure vanilla extract or vanilla bean paste.
How to Make Gluten Free Rhubarb Upside Down Cake
Here's an overview of how you'll make this sweet little cake, with the full instruction details in the recipe card lower down.
1. Prep rhubarb: Melt honey and butter in a skillet, then add rhubarb.
2. Cook rhubarb: Saute the rhubarb until slightly softened.
3. Make dry mix: Whisk together the dry ingredients.
4. Cream butter: In a large bowl, cream the butter and sugar, then add the egg and vanilla.
5. Combine: Mix in the flour mix and the milk, alternating between each addition.
6. Add rhubarb to pan: Line an 8-inch baking pan with parchment and arrange the rhubarb on the bottom.
7. Add batter: Spread the batter over the rhubarb.
8. Bake: Place in a 350°F oven and bake for 45 minutes, then cool.
Baking Tip: Use a Lot of Rhubarb!
You'll see that I call for a lot of rhubarb to make this cake, 1 pound to be exact. This may seem like a lot of rhubarb, but it will cook down a bit before you add it to the cake pan. The amount will also ensure that the entire top of the cake is covered in beautiful pink.
Tips & Variation Ideas
- Make the batter while the rhubarb cooks. As the rhubarb simmers in the honey, put together the batter (keeping an eye on the cooking rhubarb, of course). Then rest the batter while the rhubarb cools a bit, then add it to the pan.
- Line the pan with parchment. Always line your baking pan with parchment paper for super-easy removal when it comes time to take out the cake.
- How to cook the rhubarb: I like to cook my rhubarb until it's pretty soft; I like that it melts into the top of the cake during baking. But, if you wish to keep the rhubarb more firm, cook it just for a few minutes, enough that it becomes slightly tender but not soft.
- Gently dollop on the batter. The batter is thick, so you'll want to gently dollop it on top of the rhubarb in the pan, then use a rubber spatula or offset spatula to spread it out evenly.
- Use brown sugar. You can use ½ cup of brown sugar in place of the honey if you wish.
- Add citrus zest. For extra flavor, zest in 1 organic lemon or 1 organic orange (orange is a classic flavor pairing with rhubarb).
Serving Options
A scoop of vanilla ice cream, a little homemade whipped cream, a tall glass of homemade lemonade, a cup of coffee or tea; let's keep it simple.
Proper Storage
- Fridge - I like to keep this cake in the fridge because during the warmer months it will stay fresher longer. Let it sit on the counter for 10 minutes to soften up the crumb again if you like, although it's lovely eaten cold. Cover the cake with foil or place it in an airtight container and store it in the fridge for up to 5 days.
- Freezer - Let the cake sit in the fridge for 30 minutes to firm up the topping, then wrap it (or individual slices) in plastic wrap, then foil, and store it in the freezer for up to 2 months. Thaw the cake overnight in the fridge before serving.
More Rhubarb Recipes
Happy baking! If you make this recipe, I’d love to know. Please leave a comment below, reach out with any questions, and tag me on Instagram @Cucina Nicolina ❤️
Gluten Free Rhubarb Upside Down Cake
Ingredients
Rhubarb Topping
- ½ cup honey
- 4 tablespoons unsalted butter
- ¼ teaspoon fine sea salt
- 1 pound rhubarb, washed, trimmed, and sliced into long ¼-inch wide pieces (the pieces should be about the length of your cake pan)
Cake
- 1 ¾ cups gluten free flour (210 grams)
- 1 ½ teaspoons baking powder
- ¼ teaspoon fine sea salt
- ½ cup unsalted butter, at warm room temperature
- 1 cup sugar
- 1 large egg
- ½ cup whole milk
- 1 teaspoon pure vanilla extract
Instructions
- In a large cast iron pan or skillet, melt the honey and butter over low heat. Stir in the salt. Spread the rhubarb out evenly and cook until it's 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 flour, baking powder, and salt.
- In a large bowl and using an electric mixer on medium speed, cream the butter and sugar, scraping down the sides of the bowl as necessary, until light and fluffy.
- Beat in the egg and the vanilla. 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 evenly on top of the rhubarb, smoothing gently with a rubber spatula. Place the cake in the oven and bake for 40-45 minutes, or until a toothpick inserted in the center comes out clean. Check after 40 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.
Notes
- Make the batter while the rhubarb cooks. As the rhubarb simmers in the honey, put together the batter (keeping an eye on the cooking rhubarb, of course). Then rest the batter while the rhubarb cools a bit, then add it to the pan.
- Line the pan with parchment. Always line your baking pan with parchment paper for super-easy removal when it comes time to take out the cake.
- How to cook the rhubarb: I like to cook my rhubarb until it's pretty soft; I like that it melts into the top of the cake during baking. But, if you wish to keep the rhubarb more firm, cook it just for a few minutes, enough that it becomes slightly tender but not soft.
- Gently dollop on the batter. The batter is thick, so you'll want to gently dollop it on top of the rhubarb in the pan, then use a rubber spatula or offset spatula to spread it out evenly.
- Use brown sugar. You can use ½ cup of brown sugar in place of the honey if you wish.
- Add citrus zest. For extra flavor, zest in 1 organic lemon or 1 organic orange (orange is a classic flavor pairing with rhubarb).
I'd love to hear from you! Please leave me a note.