This easy Rhubarb Hazelnut Upside-Down Cake has a wonderful nutty hazelnut sponge topped with sweet, tart rhubarb. Served with a sweet blood orange syrup, this combination makes a beautifully delicious and flavourful dessert.
Rhubarb is back in town!
Firstly, let's all say a huge YAY that rhubarb's come into season. It follows on from blood oranges and the citrus season and gives us a hint of the berry season to come. I adore rhubarb and it’s intricate flavour profile that encompasses an interesting balance of tart and sweet. It’s been on my seasonal baking roster year in, year out and the whole family follow in my footsteps of loving rhubarb.
However, I understand that there are some (slightly crazy people) who aren’t sold on rhubarb. They don’t get the tartness especially when using it in a sweet dessert, they don’t like the stringy texture when cooked and they aren't convinced by the variations of candy pink, deep red and moss-green rhubarb, the latter looking a little murky when cooked.
While I don’t understand the upturned noses, I rejoice in their dislike, quite simply because there’s more for us rhubarb lovers!
Still loving those blood oranges though
Now I know that rhubarb precursors citrus season, but I’m not quite ready to say goodbye to blood oranges as over the last couple of months they've become my new favourite citrus fruit to bake with.
I still had a couple of blood oranges in my fruit bowl when I came home from picking up my rhubarb and I know as a fact that rhubarb and orange are a great combination together. As a result I decided to use the zest in the hazelnut sponge and then make a syrup out of the juice that could be drizzled on afterwards.
Umm hello ... deliciousness right there! And boy does it work so well together. Maybe, just maybe, I might turn the haters into lovers!!
Yes to hazelnut sponge!
The hazelnut sponge is so light and fluffy and yes you guessed it, nutty! I first tried the combination of rhubarb and hazelnut together when my sister-in-law bought me Donna Hay’s Season's cookbook. In it Donna shares the recipe for a hazelnut and rhubarb cake and it very quickly became a firm hit in our household.
What ingredients are in a Rhubarb Hazelnut Upside Down Cake?
- Rhubarb. Our hero of this dessert. Using forced rhubarb results in the most beautiful coloured rhubarb after baking.
- Blood Orange. Using the zest in the batter and juice in the syrup adds another dimension to this cake.
- Sugar. Provides required sweetness to the cake thickens the syrup.
- Eggs. Use large for this recipe. They bind the batter, provide lift for the fluffy texture and moisture to 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, stunning taste and texture to the batter.
- Baking Powder. Along with the eggs, the baking powder helps the batter rise.
- Salt. Always important to balance out the sweetness
How to make Rhubarb Upside Down Cake
Prepare the Rhubarb
- Prepare the cake pan. Grease with butter the bottom and sides of an 20cm (8-inch) cake pan with butter and line base with parchment paper. Dollop butter onto the parchment paper in the pan. Sprinkle with sugar.
- 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.
Make the hazelnut batter
3. Cream butter and sugar. In the bowl of a stand mixer, beat the butter, sugar and blood orange zest until pale and thickened.
TIP: by adding the zest at this point the orange zest oils will release into the butter and sugar adding extra flavour.
4. Add in the vanilla extract and the eggs beating until combined, Make sure to scrape down the sides of the bowl.
5. In a separate bowl add the dry ingredients, flour, hazelnuts, baking powder and salt and mix together.
6. Add half the flour mixture into the batter and mix through. Add the milk and chopped rhubarb and mix again. Add the remaining flour mixture and fold through until a few flour streaks remain.
7. Tip the batter on top of the rhubarb in the prepared pan and level with an offset spatula. Bake for 50-60 minutes then cool in the pan for 10 minutes. Run a knife around the cake and invert onto your serving platter, remove parchment paper and let cool completely.
Make the blood orange syrup
8. Whilst the cake is baking, make the blood orange syrup. Add blood orange juice into a saucepan along with the sugar and bring to the 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.
Drizzle half of blood orange syrup over the rhubarb and slice.
More delicious rhubarb recipes
If you love rhubarb then check more of my recipes using this amazing seasonal vegetable!
Recipe and photos have been given a slight update January 2021
Rhubarb Hazelnut Upside Down Cake
- High Sided Cake pan 20cm (8-inch)
- 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 tsp vanilla extract
- 3 large eggs , room temperature
- 120 g plain flour (all-purpose)
- 100 g hazelnut meal (ground hazelnuts)
- 1 tsp baking powder
- ¼ tsp 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
- Preheat the oven to 180°C (350°F). Grease 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. Trim rhubarb stalks to fit side by side, covering the base of the pan. Keep any remaining offcuts of rhubarb and slice into 1cm (0.5inch) pieces. Set aside.
- 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 the vanilla extract 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.
- In a separate bowl, add the dry ingredients: flour, ground hazelnuts, baking powder and salt into a medium bowl, and stir until combined.
- Add half of the flour to the batter and beat until just combined, then add the milk and mix again. Lastly, add the chopped rhubarb offcuts that you set aside earlier and the remaining flour mixture and beat until a few streaks of flour remain.
- Pour 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 skewer 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
- 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 blood orange syrup over the cake and dollop with 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.