In a large pan over medium heat, add the olive oil and onions, and cook until soft, about 10 minutes. Add the garlic and cook 2 minutes more.
Add saffron, tomatoes, bay leaves, and thyme, and cook for 5 minutes.
Add cinnamon stick, all the vegetables, salt and pepper to taste, and cook, covered, for 30 minutes, or until vegetables are soft but not too soupy. You may add a little water if needed.