This easy Rhubarb Upside Down Cake has a wonderful nutty hazelnut sponge topped with sweet, tart rhubarb. Served with blood orange syrup, this combination makes a beautifully delicious and flavourful dessert.
Rhubarb is currently available in London and when it is, I jump at the opportunity to use it. Whether it's in a simple cake like today's Rhubarb Cake, in my kids' favourite Strawberry Rhubarb Crumble Bars, or for breakfast in Rhubarb Scrolls, we love this seasonal fruit.
I first came across the combination of Hazelnut and Rhubarb from Donna Hay's Seasons Cookbook and thought of that particular combination when creating this recipe. The sponge on today's cake is light and nutty and teams well with the tart rhubarb on top.
Blood oranges are also available so I took the opportunity to make a blood orange syrup to pour over the top. If blood oranges aren't available, then regular oranges will be perfect.
🌟 Why You'll Love This Recipe
- Uses beautiful seasonal ingredients. I love to make the most of seasonal fruit when it hits the local grower's stands. Blink and rhubarb disappear until the next year, so take the opportunity whilst you can!
- Easy to make. Upside-down cake uses a simple sponge baked on top of the fruit and then flipped over. No complicated techniques are used here.
- Visual impact. The incredible pink-hued rhubarb on the cake is SO stunning. Add the dark orange blood orange syrup and you have a masterpiece to serve.
🧾 Ingredients Needed
The three ingredients that you may not have as standard in your pantry are ground hazelnuts, rhubarb and blood oranges. Blood oranges and rhubarb are definitely seasonal fruit, but in my FAQ section below, I have given some other popular fruits that you can make upside-down cakes.
- Rhubarb. Our hero of this dessert. Using forced rhubarb results in the most beautiful coloured rhubarb after baking. It's actually a vegetable but we're going to treat it like a fruit.
- Blood Orange. Using the zest in the batter and juice in the syrup adds another dimension to this cake. Use regular oranges if blood oranges aren't available.
- Sugar. Provides the required sweetness to the cake and thickens the syrup.
- Eggs. Use large eggs for this recipe. They bind the batter and provide lift for the fluffy texture and moisture of the cake.
- Vanilla. Layers the flavour in the cake.
- Milk. For moisture and to loosen the batter slightly. Yogurt or sour cream can be used as a substitute.
- Flour. Provides the batter with a little more structure than if we left it out altogether.
- Ground Hazelnuts. Provides moisture from the nuts, and a stunning taste, and texture to the batter.
- Baking Powder. Along with the eggs, the baking powder helps the batter rise to create a tender sponge.
- Salt. Always important to balance out the sweetness.
The different fruits that you can use to make an upside-down cake are endless! Here are a few ideas and some tips:
- Pineapple Upside Down Cake - the most popular by far!
- Strawberry Upside Down Cake - Hull and slice the strawberries in half placing the outside of the strawberry on the base of the cake pan.
- Banana Upside Down Cake - swap out the granulated sugar on the base with brown sugar for more caramelisation. Then peel and slice bananas in half before laying them down.
- Pear Upside Down Cake - peel and core the pear and quarter before laying them on the base. This reminds me of a Pear Tart Tatin!
- Cranberry Upside Down Cake - a festive favourite! Double the amount of zest in the sponge and use your favourite sponge batter.
👩🏻🍳 How to Make
*Be sure to see the recipe card below for the full ingredients list & instructions!*
Make the Rhubarb Upside Down Cake
STEP 1. Prepare the cake pan. Grease with butter the bottom and sides of a 20cm (8-inch) cake pan and line the base and sides with parchment paper. Dollop butter onto the parchment paper in the pan. Sprinkle with sugar (Images 1 & 2).
STEP 2. Prepare the rhubarb. Trim the stalks of the rhubarb to sit snugly next to each other in the base of the pan. With any remaining rhubarb, cut into 1 cm (½ inch) pieces and set aside (Images 3 & 4).
STEP 3. Cream butter, sugar, and orange zest. In the bowl of a stand mixer fitted with the paddle attachment, (or using hand-help electric beaters), cream the butter, sugar, and orange zest until pale and thickened (Images 5 & 6).
TIP: Adding the orange zest to the butter when it is creamed, allows for the oils to be released into the creamed butter. Alternatively, bub the zest and sugar together and then beat with the butter. You gain maximum flavour from the orange zest doing this.
STEP 4. Add in eggs. Add in the vanilla extract and eggs, one at a time, beating until combined after each addition. Make sure to scrape down the sides of the bowl periodically. The mixture may look curdled at this point but don't worry, it will come together in the next step (Images 7 & 8).
STEP 5. Mix the dry ingredients together. In a separate bowl add the dry ingredients, flour, ground hazelnuts, baking powder, and salt and mix together (Image 9).
STEP 6. Add all remaining ingredients. Add half of the dry mixture into the batter (Image 10) and mix together. Then add the milk and remaining chopped rhubarb (see note below) (Image 11) and again, mix together.
Lastly, add the remaining dry mixture and beat on low until a few flour streaks remain (Image 12). Using this as a visual point means that you won't over-mix the sponge and it will remain tender.
Note: I don't like to waste ingredients, especially not precious, hard-to-come-by rhubarb. So all the odd bits that didn't fit into the base of the cake pan, I like to chop up small and mix them into the batter. That being said, if you would prefer not to then leave these pieces out. You could stew them, make compote or freeze them.
STEP 7. Spoon into pan and bake. Tip the batter on top of the rhubarb in the prepared pan (Image 13) and level with the back of a spoon (Image 14).
Bake for 50-60 minutes until golden on top and a toothpick inserted into the centre of the sponge comes out clean. Then cool in the pan for 10 minutes. Run a knife around the cake and invert it onto your serving platter, remove the parchment paper, and let cool completely (Image 15).
Make the Blood Orange Syrup (optional)
STEP 8. Make the orange syrup. Whilst the cake is baking, add orange juice into a saucepan along with the sugar and bring to a boil stirring until the sugar dissolves. Boil for 10-15 minutes until the syrup thickens. Skim away any froth as it arises. Set aside until ready to serve (Images 16 & 17).
Once the cake has cooled, drizzle half of the syrup over the rhubarb cake and slice. You can drizzle more over each individual slice. Serve with cream or creme fraiche.
💭 Recipe Pro Tips
- Use the brightest, most colourful forced rhubarb that is available. When baked, the colour fades, so the brighter the raw rhubarb is, the better the colour post-baking.
- Make sure the butter is at room temperature. When the butter is creamed, it aerates and traps air into it which provides the lift needed when baking to provide a light sponge. Cold butter won't achieve the aeration required.
- Scrape down the base and sides of the mixing bowl periodically. I do this after adding each ingredient to the bowl. It just ensures even mixing of the ingredients into the batter.
- Get the most out of your zest by releasing the oils. Beat with the butter or rub into the sugar beforehand. Just don't wait to add the zest to the flour. You are wasting a good opportunity to create more flavour.
📋 Recipe FAQs
Centuries ago, before cake pans and ovens were ever invented, cakes were made in cast iron skillets and cooked over a fire. The cook would add the fruit and sugar into the base of the skillet and then top with the batter before placing it over an open for to bake. The cake was then a lot easier to remove by flipping it onto a serving plate.
Absolutely you can. Whatever makes life easier for you. As much as I love homemade cakes, I understand that life is life and time can be a luxury! Prepare the rhubarb as I do and lay it into the base of the pan, then follow the instructions of your cake mix box before spooning it over the rhubarb and baking. Your bake time might be different, so keep an eye on it for 40 minutes.
❄️ Storage and Freezer Instructions
To store: Rhubarb Upside Down Cake can be stored in the refrigerator for up to 4 days. Wrap well with plastic wrap and store in an airtight container in the fridge.
To freeze: Allow the cake to cool completely. Then cover the fruit in parchment paper before wrapping the cake in plastic wrap. Store in an airtight container in the freezer for up to 3 months. Thaw overnight in the fridge and bring to room temperature before serving.
🧁 More Simple Cake Recipes
If you tried this Easy Rhubarb Upside Down Cake or any other recipe on my website, please please leave a 🌟 star rating and let me know how you go in the 📝 comments below. I love hearing from you!
Rhubarb Upside Down Cake Recipe
- 15 g unsalted butter, room temperature
- 30 g granulated sugar
- 400 g forced rhubarb, trimmed (approx. 4-5 stalks)
- 180 g unsalted butter , room temperature
- 100 g granulated sugar
- 1 blood orange, zest
- 1 teaspoon vanilla extract
- 3 large eggs , room temperature
- 120 g plain flour (all-purpose)
- 100 g hazelnut meal (ground hazelnuts)
- 1 teaspoon baking powder
- ¼ teaspoon fine salt
- 60 ml milk at , room temperature
Blood orange syrup
- 180 ml blood orange juice, freshly squeezed approx, 3 to 4 oranges
- 50 g granulated sugar
Make the cake
- Prepare the cake pan. Preheat the oven to 180°C (350°F). Grease the base and sides of a 22cm (8-inch) round cake pan or springform pan and line the base with a layer of parchment paper. Smear dollops of butter evenly over the base of the lined pan. Sprinkle with sugar.
- Prepare the rhubarb. Trim rhubarb stalks to fit side by side, covering the base of the pan. Keep any remaining offcuts of rhubarb and slice into 1cm (0.5 inch) pieces. Set aside.
- Cream butter, sugar, and orange zest. In the bowl of a stand mixer fitted with the paddle attachment, beat the butter, sugar, and blood orange zest on high until pale and fluffy, about 5 minutes.
- Add in eggs. Add the vanilla extract and then the eggs, one at a time, and beat on medium to high until just combined. Scrape down the sides of the bowl after each addition.
- Mix the dry ingredients together. In a separate medium bowl, add the dry ingredients: flour, ground hazelnuts, baking powder, and salt, and stir until combined.
- Add all remaining ingredients. Add half of the flour to the batter and beat on low until just combined, then add the milk and chopped rhubarb and mix again. Lastly, add the remaining flour mixture and beat until a few streaks of flour remain.
- Spoon into pan and bake. Spoon the cake batter over the rhubarb stalks on the bottom of the prepared pan and spread evenly with a spatula. Bake for 50-60 minutes or until a toothpick entered into the centre of the sponge comes out clean. Let the cake rest for 10 minutes. Gently run a thin-bladed knife around the edge of the pan and invert the cake onto a plate. Remove the parchment and cool completely.
Blood orange syrup
- Make the orange syrup. Whilst the cake is baking, make the blood orange syrup. Add the blood orange juice into a saucepan, set over medium heat, and stir until the sugar dissolves. Increase heat and boil for 10 to 15 minutes until the syrup thickens. Make sure to skim away any froth that develops. Remove from the heat and allow to cool.
- To serve, drizzle half of the blood orange syrup over the cake. Slice and serve with a little more syrup and a dollop of cream.
All recipes are developed and tested in Metric grams. I strongly recommend that you bake using digital scales for a more accurate result. I have provided a conversion to US customary in the recipe but please note that I haven’t tested using this method.
This post was originally published in July 2019 but has been updated with new photos, new content and a revised recipe.