1. Cut the courgette in half lengthways. Using a small, sharp knife or teaspoon, carefully scoop out the flesh, trying not to cut into the skin. Do this to all eight halves.
2. Place the bulgar wheat in a small bowl and pour over 200ml of boiled water, leave for 15 minutes then drain in a sieve, squeezing out as much liquid as possible.
3. Place the lamb in a large bowl and add half of the chopped onion, the garlic, 1 tsp of the cumin and half of the parsley and mint. Add all of the chillies, the drained bulgar wheat and the pine nuts. Season with salt and a little pepper and mix together with your hands.
4. Preheat the oven to 190C/375F/gas mark 5. Press the meat mixture into the carved out courgette, squeezing in as much as you can. How much you use will depend on the size of your courgettes. If you have any filling left over, make into meatballs. Put the stuffed squash and any leftover meatballs into a large, lightly greased baking dish or roasting pan and bake for 30 minutes.
5. Meanwhile, make the sauce: heat the oil in a saucepan and fry the rest of the chopped onion until soft, about 5 minutes. Add the rest of the garlic and cumin and fry another minute. Add the wine, if using, and bring to the boil. Add the tomatoes, bay leaf, sugar and season with salt and pepper. Simmer gently, uncovered, for 20 minutes.
6. To serve, stir the rest of the herbs into the sauce and spoon over the baked courgettes. Serve any extra meatballs on the side.