1. Combine yoghurt, lemon juice, 1 garlic clove and mint in a small bowl, set aside.
2. Heat 1 tablespoon olive oil in a medium frying pan over medium high heat, add mushrooms. Cook for 4 minutes, add remaining garlic, cumin and coriander and cook for a further 1 minute or until mushrooms are fragrant and golden. Allow to cool slightly.
3. Place chickpea, carrot, parsley and mushroom mixture in the bowl of a food processor and blend until just combined. Shape into 4 patties, dust in flour.
4. Heat remaining oil in a large frying pan. Cook patties for 3-4 minutes each side or until crisp and golden.
5. Place base of rolls on serving platter, spread evenly with yoghurt, top with lettuce, mushroom patty, cucumber and top of roll to serve.