For the mango and avocado salsa: Combine the mango, avocado, tomatoes, jalapeno, basil, lemon juice and zest, coriander and salt and pepper to taste in a large bowl and mix well. Chill in the refrigerator for 30 minutes before serving.
Remove the lamb from the refrigerator 30 minutes before cooking. Preheat a grill or grill pan over medium heat. Remove the lamb from the marinade, allowing the excess to drip off. Grill on all four sides until slightly charred, about 3 minutes per side for medium-rare. Check the internal temperature with a meat thermometer. For medium-rare the temperature should read 130 degrees F. Remove from the grill and let rest for 5 minutes.
To serve, spoon about 1/4 cup of the yogurt sauce onto each plate. Place the lamb chops on the yogurt sauce. Top with some salsa. Reserve the remaining yogurt sauce and salsa for another use.