Cut off the fins and tail from the snapper, and give 2-3 deep slits on each side. Sprinkle with coarse sea salt and set aside. (You can keep the fish in the fridge if not cooking within 30 minutes)
Preheat the oven to broiler setting.
Line a broiler-safe pan with foil and place a rack on top. Spray the rack with oil. Place the red snapper on top and pour 1/4-1/2 cup of water in the pan. Place the pan in the oven so that the fish will sit about 4" below the heat source. Broil 8-10 minutes on one side. Flip the fish to the other side and continue to broil until it gets deep brown and the meat looks flaky, about 7-8 more minutes.
Meanwhile, in a small mixing bowl combine chili paste, soy sauce, sugar, garlic, ginger, plum extract (or lemon juice), sesame oil, sesame seeds, and green onion. Mix well.
When fish is done, spread the chili mixture sauce over the fish and serve warm with rice.