Preheat the oven to 180°C.
Cut the courgette in half (lengthwise) and put them on a baking tray. Scoop out the soft flesh, creating a boat shape. Brush the inside with some olive oil and bake for 10 minutes.
Meanwhile, chop the onion and pepper and gently sauté until soft. Add the spices, stir for a few seconds, then add the tomato purée with a dash of water. Add the seafood and gently cook, under cover, for about 10- 15 minutes.
Take the courgette out of the oven and set aside.
Add the spinach or your chosen green vegetable to the stew, cook for a couple of minutes – if the sauce is too thick, reduce it by turning up the heat and removing the lid.
Add a spoonful of chopped basil leaves and taste. Season with salt and pepper (and chilli flakes perhaps) to your liking.
Stuff the courgette with the seafood mixture. Put a couple of basil leaves on top, then cover with mozzarella slices.
Set the oven to grill and cook for a few minutes until the cheese has melted and slightly browned.