Name: Microwave Summer Berry Crumble for One
Prep time: 6 min
Cook time: 9 min
Total time: 15 min
Yield: 1
Cuisine: British
Ingredients: 150 grams (1 cup) frozen summer berries; 1 tbsp lemon juice (fresh or bottled); 20 grams (1.5 tbsp) granulated sugar (split); 15 grams (1 tbsp) cold salted butter; 35 grams (1/4 cup) plain flour; 10 grams (2 tbsp) rolled oats

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This microwave berry crumble uses a frozen summer berry mix to create a rich, fruity, sweet and tart filling with a perfect crispy crumble topping! It’s the perfect single-serving summer dessert.

a spoonful of berry crumble over the dish of crumble

The berry layer can be made with fresh berries, but personally I actually prefer frozen. They’re more convenient! It means that you can use the mixed berries all year round, which is a major advantage.

For the crumble topping, you can really flavour it how you like. I chose not to use cinnamon since this is a summer version of my microwave apple crumble. However, if you fancy cinnamon then go for it!

I’m such a fan of single-serving desserts – and for good reason! I’m starting to develop a collection:

… with more soon to come! So, if you’d like to see more then make sure to subscribe to my email list!

dish of berry crumble with a spoonful taken, showing berry jam filling

What do I need to make this frozen summer berry crumble?

You don’t need much to make this crumble – it’s super simple and cheap!

Frozen mixed berries – I used a summer berry mix, but you can use any combination you like! I’d particularly recommend anything with blackberries, blackcurrants, raspberries, redcurrants, blueberries or strawberries. The mix I used had most of these and it was just gorgeous!
A little bit of lemon juice – bottled juice is just fine here. It helps to break down the berries to release their juices, as well as adding a touch of acidity. You could avoid it if your berries are fresh, or reduce it if you prefer a sweeter crumble.
Granulated sugar – you could use brown sugar. However, I prefer granulated sugar with the berries since it keeps the flavour lighter and fresher. Some of this is also for the berry mixture to add with the lemon juice. This is to help break the berries down to form a sort of jammy consistency.
Plain flour for the crumble topping to make the breadcrumb mixture
Cold butter – it’s very important that it’s cold to make the breadcrumbs. I used salted butter, so if you use unsalted butter then make sure to add a small pinch of salt to the topping mix
Rolled oats – these are just for texture in the topping, so they’re completely optional!

If you prefer a sweeter crumble, then you may want to add a little bit of extra sugar to the berry filling. Or, you could make the topping sweeter by adding more sugar there. It’s up to you!

In this case, you might be able to make it sweet enough by choosing berries that are naturally less acidic – avoiding things like redcurrants that are more tart. I’d recommend using strawberries and raspberries for sure in this case, along with possibly some blueberries and blackberries.

You can make this frozen berry crumble vegan by using vegan butter in place of regular butter. I’m afraid that I’m no expert on gluten-free crumbles though, but I would have thought that a gluten-free plain flour blend should work just fine. If you are gluten-free then make sure to check that your oats are gluten-free too if you’re using them!

What do I need to make this recipe?

You don’t need much in the way of equipment:

kitchen scales and measuring spoons to measure out the ingredients. You can use cups, but they’re far less accurate.
a microwave-safe bowl to make the crumble filling in – and some more bowls as you’ll need another one to make the crumble topping
and a microwave, of course! I used a 900 Watt one, so if yours is different then timings may vary.

How do I make this microwave berry crumble?

The method for this recipe is actually super simple. It’s very similar to my microwave apple crumble (the topping is made the same way) crossed with a microwave jam recipe to make the berry filling.

Add the berries to a bowl with the lemon juice and 1 tsp of granulated sugar. Stir to combine and microwave for 5-6 minutes, stirring every 2 minutes. It should have the consistency of a lovely, thick jam.
To make the topping, rub together the butter and flour to form a mix that looks like small breadcrumbs. Stir in the rest of the sugar and the oats.
Top the berry mixture with the topping mix and microwave for 3 minutes or until cooked. Or, to get it to turn golden and properly crisp, broil/grill until just golden.
Serve immediately – ideally with ice cream or creme fraiche!

If you’re using unsalted butter then add the salt along with the flour.

If you choose to use cinnamon in the topping then add it to the topping with the sugar.

One important note: if you’re scaling up this recipe to feed more people then it’s important to note that the berry jam mixture will take longer to cook as there’s more moisture that will need to evaporate.

On the topic of the berry jam, make sure to use something to prevent it from splattering all over the microwave as it cooks! The berries have a tendency to sort of explode, squirting juice everywhere so don’t say I didn’t warn you!

How can I customise this single-serving crumble?

There are so many ways that you can customise this crumble! Plus, since it’s a single-serving one, you can test new ideas out without having to worry about too much waste if it goes wrong!

For starters, as I already mentioned, you can adapt which berries you use to suit how sweet or tart you want the crumble to be.

If you’d like a sweeter crumble then I’d recommend using more raspberries, strawberries and blueberries plus an extra teaspoon of sugar to break down the berries if you like it super sweet.

Or, for a more tart crumble, try using lemon zest along with the juice, increasing the juice, and using more tart berries like redcurrants, lingonberries (which are just delicious!), cranberries and blackberries.

To customise the topping, you could add chopped nuts, spices like cinnamon or ginger, swap granulated sugar for brown sugar or swap rolled oats for toasted oats for an extra crispy topping.

Enjoy!