Preheat your grill. Put grated lemon or lime rind, juice, minced garlic, salt and pepper and dash of olive oil in a baking dish. Dredge salmon filets in the marinade and then place on the grill skin side down, for 10-12 minutes.
Cover your grill after the first few minutes so the fish cooks evenly throughout. While the fish is cooking, heat a small pan with a thin coating of olive oil on the stove or grill under medium heat. Immediately add chopped onion, chili, cherry tomatoes and chopped lemon or lime and sauté for 4-5 minutes.
Serve salmon over rice, if desired, and top with the salsa from the pan. Garnish with the cilantro if you wish.