Delicious oaty Blackberry Apple Crumble Slice with a stunning layer of compote. Sweet, fruity and perfect for foraged blackberries. Gluten free; optional dairy free.
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A Blackberry Apple Crumble Slice with foraged fruit
This Blackberry Apple Crumble Slice is full of Autumnal flavours and fun. Not only is it fruity and delicious, but it contains FREE food… grabbed from the hedgerows and snaffled orchard windfalls.
Foraging for blackberries is one of late summer’s delights. Simply pick an afternoon with the gradually fading warmth of the end of summer sun, grab a couple of tubs, pull the kids out of the door and plunder nature’s seasonal gift.
It makes fantastic family entertainment and a shared experience unlike any other… Fresh air is combined with anticipation and excitement at spotting blackberry brambles… Care and caution exercised as berries are picked, making sure they aren’t squashed and squeezed… An occasional sneaky berry tasting along the way… And best of all, the thrill of going home with a mountain of free fruit.




Tips for Picking blackberries
It seems that brambles grow wild just everywhere these days. But although you can probably walk a short distance from your front door and find berries ready and ripe, there are a few rules that are worth considering.
Picking the best blackberries for Blackberry Apple crumble slice
- Try to avoid blackberries growing by busy roads. Tempting as it may seem to park up, pick and run, these berries have been exposed to endless pollution from exhaust pipes at close quarters. The fruit may look juicy, but you’ll end up consuming an abundance of chemicals which aren’t going to be good for health.
- Instead, find a blackberry source which is as far into the countryside as you are able to venture. It’s a great excuse to get some cleaner air and the brambles are likely to be more fruitful as well.
- If you walk as part of your lifestyle, make a note of local places where you spot brambles growing throughout the year. I say make a note, because if you are anything like me, you won’t be able to remember come August.
- Even in the countryside, avoid berries at ground level, especially of bushes in areas popular with dog-walkers… Urinated berries aren’t a pleasant thought.
- Try to pick only the berries that are fully black. And if they are too soft, discard. That way, you get sweet, ripe berries that don’t spoil too quickly.
- Give everyone with you their own container. It helps little ones feel more independent and prevents over-piling the berries. Too many soft berries piled high results in squashed fruit.




How to wash Foraged blackberries
- Bear in mind that washing the blackberries will likely start the spoiling process. As with other soft berries (like raspberries) the washing process is likely to cause some bruising and breaking. So, try to wait on washing until ready to use or freeze.
- You may not like this bit… but hedgerow blackberries are home to lots of bugs (including tiny worms and larvae). But that’s not a problem, if you wash them thoroughly.
- Thorough washing goes beyond rinsing in a colander. Gently transfer the berries to a large container of cool water (also see tip below) and swirl around to remove loose debris. Scoop this off the top, before gently draining with a colander and repeating the rinse process twice more.
- To encourage the bugs and larvae out of their berry hiding places, use a solution of vinegar and water in the first rinse bowl. I use white wine vinegar (it’s cheap) at a ratio of about 1 part vinegar to 3 parts water. Swirl and soak for about half an hour before scooping off debris, draining and rinsing a couple of times in clean water bowls.
- Once washed, drain thoroughly to get rid of as much water as possible and store in a container in the fridge. Try to use within a day or two, or freeze straight away…
- To freeze, spread on a tray and if possible, fast freeze (with the freezer at its lowest temperature (-23 C/-10 F is ideal)) before transferring to airtight bags/containers.




Why love Blackberry Apple Oat Crumble Slice?
One of the things I particularly love about making this oaty blackberry apple crumble slice is that the biscuit base and crumble top start with just one mix. That cuts down time and effort massively. And you can make your blackberry and apple compote for the fruit layer well ahead of time. Just pop it in the fridge (or even freeze for the winter months), until ready to use.
The flavours and textures in blackberry apple crumble slice are also bold and incredible. From sweet yet tangy, to crunchy and crumbly but soft. The oats are creamy. The nuts add depth and earthiness. Using brown sugar and a sprinkling of white chocolate chips offers sweet caramel overtones.
Sandwiched in-between is a thick fruity layer of cinnamon spiced blackberry-apple compote. Simply perfect served with custard or ice cream as a dessert or pudding.
What else can you make with foraged blackberries?
Whilst this blackberry apple crumble slice is totally divine, there are loads of ways to use foraged blackberries. Here’s a few ideas to whet your appetite…
- Blackberry Cheesecake with Coconut (No Bake) (Gluten Free Alchemist)
- Apple & Blackberry Crumble (Gluten Free Alchemist)
- Chicken, Nectarine & Blackberry Salad (My Gluten Free Guide)
- Blackberry Ice Cream with Dark Chocolate – No Churn (Gluten Free Alchemist)
- Blackberry Barfi with Coconut & Rose (Tin & Thyme)
- Lavender Blackberry Panna Cotta with Blackberry Poached Pear (Gluten Free Alchemist)
- Blackberry Clafoutis (Gluten Free Alchemist)
- Blackberry Crumble Fool (Glutarama)
- Apple Blackberry Curd (Gluten Free Alchemist)
- Sweet Dessert Yorkshire Pudding with Vanilla Sautéed Pear, Walnuts and Blackberry Coulis (Gluten Free Alchemist)
- Mixed Berry & Apple Jam (Gluten Free Alchemist)
- Blackberry Meringues with Rum Chantilly Cream (Supergolden Bakes)




Can I make this crumble slice with wheat flour as well as gluten free?
Yes. If you are not gluten free, substitute the gluten free flour blend for plain wheat flour and remove the xanthan gum from the list. You can use ‘normal oats’.
If you are gluten free, choose a good quality gluten free flour blend. I always make my blackberry crumble bars with Gluten Free Alchemist Flour Blend A. It’s mild in flavour and has a good balance that isn’t too gritty. But other gluten free flour blends should work fine.
If you are Coeliac or need a gluten free diet for health reasons, make sure you use certified gluten free oats.
Can I make Blackberry Apple Crumble Bars Dairy Free?
Yes. To make these crumble bars dairy free, simply make sure your ‘butter’, chocolate and milk are all dairy free or vegan.




Made Blackberry Apple Crumble Slice?
Let me know if you make blackberry apple crumble slice. It’s always been well received here. Send me an email, tag me on social media (links at the top of the page) or leave a comment below. And don’t forget to follow and subscribe to Gluten Free Alchemist for the latest recipes.




More Great Blackberry Recipes at Gluten Free Alchemist
Blackberry Apple Oat Crumble Slice
Key equipment
- sharp vegetable knife
- large saucepan
- oven + hob
- 9 inch (23 cm) square non-stick baking tin
Ingredients
Blackberry Apple Compote
- 1 large cooking apple peeled, cored and cut into small pieces
- 430 g blackberries washed – fresh or frozen
- 75 g golden caster sugar or more to taste
- 1½ tsp ground cinnamon
- 1 tsp arrowroot powder mixed with 1 tablespoon water
Biscuit Base and Crumble Top
- 350 g gluten free flour mix I use GFA Blend A – See NOTES (or use an alternative flour blend)
- 1 tsp xanthan gum
- 1 tsp GF baking powder
- 225 g unsalted butter (or DF alternative) cold and cubed
- 350 g soft light brown sugar
- 175 g oats certified gluten free if required
- 50 g flaked almonds toasted
- 100 g white chocolate chunks (DF if required)
- 1 large egg UK large – lightly beaten
- 1 tbsp milk dairy or non-dairy
Instructions
Preparation
- Prepare a 9 inch square loose-bottomed, non-stick baking tin, by base-lining with baking paper or lightly greasing.
- Wash and prepare the fruit and toast the flaked almonds.
Blackberry Apple Compote
- Put the cubed apple, blackberries, caster sugar and cinnamon into a large saucepan and bring to a simmer.
- Simmer until the fruit is soft and broken down and the liquid has reduced.
- Add the arrowroot-water mix and continue to stir until the mixture thickens.
- Turn off the heat and set aside.
Biscuit Base and Crumble
- Pre-heat the oven to 180 C/350 F/Gas 4.
- Weigh and mix together the flour, xanthan gum and baking powder in a large bowl, making sure any lumps are broken down.
- Rub the butter into the flour mix until it resembles breadcrumbs.
- Add the brown sugar, oats and almonds and stir thoroughly.
- Remove about a quarter to third quantity of the mix to a separate bowl.
- Mix the chocolate chunks into the smaller portion and set aside.
- Add the egg and milk to the larger portion and mix with a wooden/silicone spoon until completely blended and beginning to form clumps.
- Put this mixture into the baking tin and press down with the back of a spoon or glass to make a biscuit base which is smooth and even.
- Bake for 15 minutes, then remove from the oven.
- Spoon the blackberry apple compote onto the biscuit base and spread into a thick even layer.
- Top this with the remaining crumble-white chocolate mix and bake for a further 20 to 25 minutes until golden.
- Serve hot, warm or cold. Delicious with cream, custard or ice-cream.
Notes
Nutrition
© 2019-2023 Kate Dowse All Rights Reserved – Do not copy or re-publish this recipe or any part of this recipe on any other blog, on social media or in a publication without the express permission of Gluten Free Alchemist
Blackberry Apple Crumble Slice shared with :
- Meatless Monday with Confessions of a Mother Runner and A Whisk & Two Wands
- What’s For Dinner #267 with The Lazy Gastronome
- Cook Blog Share with Recipes Made Easy
- Fiesta Friday #343 with Angie and Spades, Spatulas & Spoons
- Full Plate Thursday #499 with Miz Helen’s Country Cottage
- Create, Bake, Grow, & Gather #436 with Shabby Art Boutique
Previously Shared with : Vegetable Palette with Seasonal Shaheen.
Your awesome post is featured on our 500th Full Plate Thursday! Thanks so much for sharing with us, we will all enjoy your post. Hope you have a great weekend and come back to see us real soon!
Miz Helen
Thank you so much Helen. I feel very honoured! xx
These sound and look delicious. We’re going blackberry picking later so will be giving these a try!!
Thank you Beth. Enjoy xx
Can I have a few please? They look absolutely delicious!
Ha ha yes! For sure. They are very moreish xx
Thanks for sharing at the What’s for Dinner party! I sure hope to see you at the new one tomorrow. Have a great afternoon.
Thank you so much Helen. It’s such a lovely recipe that I hope people enjoy it xx
You’ve made this impossible, two winning recipes! I am pinning both.
Thank you Liz. Blackberries are such a star fruit! x
Even better than blackberry and apple crumble – portable blackberry and apple crumbe! Thanks for sharing on #CookBlogShare
Oh yes! Definitely better than a straight crumble. And the flavours are amazing xx
I love the colour! It’s the perfect recipe for this time of year.
Me too Helen. Somehow the colour makes it even more incredible… but the flavour shines too x
This sounds divine – a perfect Autumn recipe!
Thank you Kat. It’s Autumn through and through x
Blackberries are really good right now. What a delicious combination. Thanks for linking up for meatless Monday
You’re welcome Deborah. The blackberries are amazing this year x
I keep sending the kids out to fetch more berries from down the road – need to send them out again now so I can make this too hahaha
Ha ha! Yes… I need to get some more too… Keep getting recipes ideas…. xx
What a stunning recipe and photographs! I grew up on wild foraged fruit (it was the only fruit I ever had, to be honest, mother was not a fruit and vegetable person!). Loved the stuff 🙂 Thank you for sharing with Shop Local and apologies to taking so long to pop by to comment. Round up will be posted soon!
Thank you so much Elizabeth. And thanks for sharing onward! We are all so busy…… Thanks for hosting!
How did I miss these when you first published them?! They look wonderful – the colours are so bright and pretty. I love your photos too on the dark background.
Thanks Laura…. I admit I was a bit worried about the photos, as the light wasn't great…. but they turned out ok!
Thanks for taking the time to enter – a petite treat indeed!
You're welcome…… My pleasure….. I got to eat them!
We have been on similar missions recently! I wouldn't have thought of putting white chocolate in. Don't tell my daughter on what she has missed out on!
Haven't we?! It always makes me smile when I see someone else has had the same inspiration! The white chocolate definitely adds an extra decadence, but I promise not to 'tell'……
Oh I could do with taking a slice of this with me today as I get ready to go into work, yum -cake of sorts for breakfast. I have yet to forage for blackberries. I make a raspberry oatie bars quite a lot when I lived in Scotland, you have reminded me of them once again. Thank you for sharing with vegetable palette.
You're welcome Shaheen. I've made something similar with raspberries too. You can use all sorts of fruit and putting them into a slice makes a sort of 'carry about crumble'….. perfect for those lunch (or breakfast) boxes!
Kate, the round up will be up tonight – so sorry about the delay. Hope you will participate this month too.
Oh just today I was tasting the first blackberries whilst walking in the countryside. There are so many in the UK! I think I will go foraging soon and make something with them. I really like this crumble! Looks so delicious with that gorgeous bright colour. Your photography is really good too!
Thank you Alida. I can't believe the fruity bounty out there at the moment. It is definitely a great year for growing! Go grab some before the birds get it!
What gorgeous photos – they look like they could be from a cookbook!
Oh thank you CC. That's really kind of you!
These do look fantastic. I have some very local blackberries from my garden in the freezer at the moment and I'd love to make something like this with them.
You should Corina. It's such a lovely way to eat them (and a bit different form the usual crumble or pie)!
What a fabulous looking bake. Stunning colour to the berries. I agree there is something special about being able to forage for fruit. My parents used to have wild blackberry and plum trees near where we lived when I was growing up and I have many happy memories picking fruit in the autumn.
These look so delicious
Thanks Katie. Picking autumn fruit is such fun. I often go to the local orchards when the commercial picking has been done too and scrum the left-over apples and pears!