Remove any unsightly leaves and spots from the leek, cut into rings, wash and drain.
Peel and dice the onion.
Peel the garlic and crush it with a pinch of salt in a mortar.
Core the peppers and cut into bite-sized pieces.
Cut the aubergines, courgettes and tomatoes into bite-sized pieces.
Peel the potato and cut into bite-sized pieces.
Heat the olive oil in a large saucepan over a high heat and sauté the diced onion in it for about 30 seconds.
Turn the heat to medium and add the tomato paste, bay leaves, harissa (optional), cinnamon and cloves and fry briefly.
Add the aubergine and tomatoes and stir-fry for about 3 minutes.
Add the remaining vegetables and sauté for another 3 - 5 minutes, stirring occasionally.
Add the tomato pulp / strained tomatoes, thyme, crushed garlic, chickpeas and water and simmer for approx. 20 - 25 minutes on medium heat with the lid closed.
Season to taste with salt and pepper.
If necessary, remove fresh thyme sprigs and bay leaves before serving.