To prepare relish, combine first 12 ingredients, tossing well to coat.
To prepare fish, brush fish with 1 tablespoon oil; sprinkle evenly with 1/2 teaspoon salt and 1/8 teaspoon pepper. Heat a nonstick skillet over medium-high heat. Coat pan with cooking spray. Add fish to pan. Cook 4 minutes on each side or until fish flakes easily when tested with a fork or until desired degree of doneness. Serve fish with relish.