Rhubarb Crumble Cake Bars are a tray bake version of a classic British dessert. This moist cake is topped with roasted rhubarb and scattered with a tasty crumble layer.
What is rhubarb?
Rhubarb is a leafy green plant with pink stalks popular in the UK. The leaves are inedible as they are poisonous so only the stalks are used. Technically rhubarb is a vegetable but it is largely considered a fruit because it is usually used in desserts and cooked with sugar.
You can grow and buy forced or unforced rhubarb. Forced rhubarb is grown in the dark which promotes the plant to produce lighter pink, sweeter stalks.
When is rhubarb in season?
Forced rhubarb is in season first, usually around mid January until March. This is popularly grown in Yorkshire in the UK and is well known for it’s fantastic bright pink colour.
Rhubarb that isn’t forced comes into season from March until September. This is the rhubarb that I use because my parents and Mr Curly’s Nan both grow it.
I love freezing rhubarb because it means I have a supply year round and can enjoy it when it isn’t in season anymore. You also don’t want rhubarb to go to waste so it is a great way to save it for later.
What are Rhubarb Crumble Cake Bars?
These Rhubarb Crumble Cake Bars are a delicious way of incorporating one of my favourite British desserts into a tray bake.
Rhubarb Crumble Cake Bars are a layer of tasty yoghurt cake topped with delicious roasted rhubarb. They are then finished with a generous scattering of crumble topping.
The cake bars are baked in a tray bake tin which makes it incredibly easy to cut them into equal pieces.
Why roast the rhubarb?
Roasting rhubarb is a great way of using it in baking. Adding raw rhubarb to a cake could mean the liquid from the rhubarb seeps into the cake. This excess juice could make the cake bars soggy – not ideal!
I like to dot the roasted rhubarb in a nice layer across the whole cake before adding the crumble topping. I do this because I like to see visible layers of the cake, rhubarb and then crumble topping.
You could marble the rhubarb into the cake batter if you wanted using a skewer or a butter knife if you prefer.
WHICH TYPE OF YOGURT IS BEST TO USE FOR THese rhubarb crumble cake bars?
I love adding yogurt to cakes. Cakes with yogurt are slightly more dense than really fluffy cakes like Vanilla Cupcakes. Although cakes with yogurt might not be as fluffy, they are really moist and delicious.
You can use whichever plain yogurt you like. I have used both natural yogurt and Greek yogurt as well as fat free versions of both. They all work really well and I haven’t been able to notice any differences.
Check out my Raspberry & Vanilla Swirl Sheet Cake and Blackberry Crumble Loaf Cake for other tasty cakes using yogurt.
WHAT TO DO WITH EXCESS RHUBARB
If you find yourself with more rhubarb than you can use, I recommend freezing it. I get given so much rhubarb each year I can’t use it all at once so have to save some for later.
I wash the rhubarb and trim it into similar sized pieces and freeze it. I’ve done this for a number of years now and it always turns out great.
It is up to you whether you want to defrost it or not, you could just add it straight to the baking tray for roasting. You also don’t want rhubarb to go to waste so it is a great way to save it for later.
How to serve these Rhubarb Crumble Cake Bars
These cake bars are the perfect mid afternoon treat – or an anytime of day snack when you feel the need for cake! They are also really easy to transport so would be a great addition to a picnic or for lunchboxes.
They are also very easily turned into a desert. I would warm the cake bars through slightly and serve them with cream, ice cream or homemade custard.
How many cake bars does the recipe make?
Well that does depend entirely on how big you want to cut the bars! I think it does depend how you will be eating them as to how big you cut them.
If you are going to be eating them as a tasty snack, I would recommend cutting them into 24 bars. You could definitely get away with cutting the bars a bit smaller if they are for children’s lunchboxes.
If they are going to be served as a dessert, you could definitely cut them a bit bigger. But it really is up to you – cut them as big or small as you like!
HOW LONG WILL THIS CAKE KEEP FOR?
One of the great things about adding yogurt to a cake recipe is that it keeps it moist and delicious for longer. Keep these Rhubarb Crumble Cake Bars in an airtight container for 4-5 days.
The crumble topping will soften the longer these bars are kept for. I don’t mind this at all but it is worth mentioning.
You could also freeze these bars if you didn’t want to eat them all. I would wrap them individually so you can defrost them as and when you need a sweet treat.
Let them defrost at room temperature for a few hours and then they will be ready to eat.
OTHER RECIPES YOU MIGHT LIKE
- Rhubarb & Vanilla Cake
- Rhubarb Crumble Muffins
- Mini Rhubarb Crumble Pies
- Oaty Rhubarb & Port Crumble
- Roasted Rhubarb Ice Cream
- Blackberry Crumble Loaf Cake
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Rhubarb Crumble Cake Bars
Rhubarb Crumble Cake Bars are a tray bake version of a classic British dessert. This moist cake is topped with roasted rhubarb and scattered with a tasty crumble layer.
Ingredients
For the roasted rhubarb
- 600 g rhubarb
- 70 g caster sugar
For the cake
- 250 g caster sugar
- 250 g margarine
- 150 g low fat Greek yogurt
- 1 tsp vanilla extract
- 4 eggs
- 250 g self raising flour
For the crumble topping
- 100 g self raising flour
- 85 g unsalted butter
- 50 g light brown sugar
Instructions
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Begin by roasting the rhubarb – heat the oven to 180ºC (fan, 200ºC non fan). Rinse 600g rhubarb and dry off any excess water. Trim the ends and cut into pieces roughly one inch in length
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Put the rhubarb on a baking tray and sprinkle over 70g caster sugar. Toss together making sure all of the rhubarb is coated and then lay the rhubarb out in one layer
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Cover with foil and bake for 15 minutes before removing the foil and giving the rhubarb a quick stir. Return to the oven without the foil for a further 5 minutes
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Drain the rhubarb using a colander and leave to cool. Reserve the liquid
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Reduce the oven temperature to 160ºC (fan, 180ºC non fan) and line a 20x26cm (8×10") tray bake tin
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Beat the 250g caster sugar and 250g margarine together
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Add 150g Greek yogurt, 1 tsp vanilla extract, 4 eggs, 250g self raising flour and mix until combined
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Spoon the cake mix into the prepared tin and smooth until level. Leave to one side
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In a large bowl, add 100g self raising flour, 85g unsalted butter and 50g light brown sugar. Rub the ingredients together until you form large crumbs
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Add blobs of the roasted rhubarb on top of the cake mix
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Scatter the crumble topping over the rhubarb. Bake in the oven for 35-40 minutes until a cocktail stick comes out clean
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Leave to cool in the tin for approximately one hour before turning out and leaving to cool completely on a wire rack. Cut into squares and serve
Recipe Notes
You can use unsalted butter or margarine for both the cake and the crumble topping – both work just as well.
Keep the cake in an airtight container for 4-5 days.
Nutritional information is given as a guide only and may vary.
Paul says
Having tried these cake bars both as a tasty sweet with an afternoon coffee and as a dessert with ice cream, I am happy to recommend them to everyone. A great taste with a bit of a sharp tang from the rhubarb, something I found to be just what I was looking for in an easy to follow recipe
Curly says
So pleased you liked them 🙂 They make a great dessert as well as snack!
ELAINE says
I was lucky enough to be a taste tester for these.
Really, really enjoyed them. I love rhubarb crumble and this was a perfect snack size version. Very versatile too as could make a lovely dessert too drenched in cream
Curly says
Glad you liked them 🙂
Janice says
My garden rhubarb is just ready to pick so this recipe came at the right time! Absolutely delicious with the sharp and sweet merging together.
Curly says
I’m getting inundated with it at the moment! Just washed and chopped 1kg to put in the freezer so I can make these throughout the year.
Marita says
I never roasted rhubarb, but I will try it now. I love everything with crumble, so I cannot wait to make it. x
Curly says
I love roasting rhubarb, it is how I use it in all of my bakes. Hope you like them 🙂
Choclette says
Love rhubarb and it makes fantastic cakes. Your crumble cakes look so delicious that I’m almost tempted to dash off to the allotment right now to pick some.
Pinned x
Curly says
It really does! Thank you 🙂
Lesley says
What a delicious recipe, I love any bake that contains rhubarb and this one really does make this best of new new season rhubarb. A lovely light cake.
Curly says
Thanks so much Lesley.
Karen says
I love rhubarb season – and my rhubarb is all up now – these look fabulous for the rhubarb season!
Thank you for joining in with #CookBlogShare this week, Karen
Curly says
I’m getting lots from my parent’s and husband’s Nan so I can see myself making these a lot!
Kat (The Baking Explorer) says
They look absolutely delicious! Rhubarb is so tasty in cakes!
Curly says
Thanks Kat. I love using it in baking 🙂
Chloe says
Love this twist on classic crumble – much more suitable for spring days too!
Curly says
Definitely! And there are only so many crumbles you can make!
Deanna says
Please show the measurements in cups and tablespoons.
Conversion would be appreciated!
Curly says
Hi Deanna, I do not use cups etc as I find weighing scales more accurate. You can find conversion tables online if you wish to use cups.
Sophie says
Thanks for the lovely recipe, my house is smelling lovely 🙂
I’m just wondering, any suggestion of something to make with the leftover rhubarb liquid?
Curly says
So pleased you like them Sophie. I actually like adding to to lemonade for a tasty drink. But you could eat it with yogurt too.