Heat oil in a medium saucepan over medium heat. Add onion, bell pepper and garlic and cook, stirring occasionally, until beginning to soften, about 3 minutes. Add lamb, turkey and salt and cook, stirring and breaking up with a spoon, until no longer pink, about 4 minutes. Add tomatoes and cook, stirring occasionally, until they have released their liquid and are beginning to break down, about 4 minutes more. Add chickpeas, harissa (or chili powder) and cinnamon and cook, stirring, 1 minute more. Serve garnished with cilantro (or mint).