Combine tomato, 1/2 teaspoon salt, and next 7 ingredients in a large bowl; set aside.
Sprinkle salmon with pepper and remaining 1/4 teaspoon salt. Heat oil in a large nonstick skillet over medium-high heat. Add salmon; cook 3 to 5 minutes or until golden on both sides but not cooked through, turning once. Transfer fish to a plate.
Add onion to skillet; cook 3 minutes, stirring constantly. Stir in tomato mixture; cook for 4 minutes or until liquid begins to thicken, stirring constantly. Gently place salmon on top of tomato mixture. Cook 2 to 3 minutes or until desired degree of doneness. Sprinkle with mint. Serve with hot cooked couscous.
*The green pitted salad olives (not to be confused with pimiento-stuffed Spanish olives) have a similar flavor to--and may be substituted with--ripe black olives.