Fill a large saucepan with water and bring it to the boil. Add the broad beans, return to the boil and cook for 3–4 minutes until tender. Drain the beans, refresh under cold running water and transfer to a bowl.
Add the olive oil, lemon juice, most of the preserved lemon rind and mint to the bowl with the broad beans. Toss well and season with salt and pepper. Garnish with the remaining preserved lemon rind and mint. Serve as a side salad to accompany tagines.