Step 1

Stir berries together with 1 tsp (5 grams) of the sugar and all of the lemon juice in a microwave-safe bowl.

Step 2

microwave for 5-6 minutes, stirring every 1-2 minutes, until the mixture forms a thick jam-like consistency.

Step 3

to make the crumble topping, rub together the butter and flour with your fingers or a fork to form small crumbs. Stir in the rest of the sugar and the rolled oats.

Step 4

top the berry mixture with the crumble topping mixture and microwave for 3 minutes or until cooked. Alternatively, grill/broil until the top is golden-brown and cooked through.

Step 5

Serve immediately