1. Preheat a grill to a moderate heat.
2. In a large bowl combine together the mince, onion, breadcrumbs and dried mint, season well.
3. Shape into 8 flat patties, brush lightly with oil and grill for 8-10 minutes on each side.
4. Lightly toast the burger buns, fill with the burgers, top with one of the chutneys and crisp iceberg lettuce. Serve immediately.