Thinly slice the onion and mince the garlic.
Cut the courgette, red pepper and aubergine into cubes. Roughly chop the tomatoes. Pick the basil/parsley leaves and set them aside, then thinly chop the stalks.
In a large casserole dish, heat some olive oil and stir the aubergine pieces for 5 minutes, then set aside. Then cook the courgette pieces for 3 minutes and set aside. Then cook the pepper pieces for a couple of minutes and set aside. It’s important not to overcook the veggies.
Heat another spoonful of and add the onion slices. Gently sauté them for 5 minutes, then add the thyme leaves (or dried herbs of your choice), the chopped fresh tomatoes, garlic and the vinegar. If the tomatoes are not ripe, add a small spoonful of sugar. Cook over medium heat until sticky (for about 3-5 minutes).
Add the tinned tomatoes or tomato purée, let it bubble for a few seconds, then return the fried aubergine, courgette and red pepper. Season to taste.
Cover the pan and simmer over low heat for about 20-30 minutes or until the veggies are tender and the sauce is thick and sticky. Taste and season with salt and pepper, if needed.
Serve with chopped basil or parsley leaves scattered on top.