Grilled Tuna with Wilted Spinach

1. Rinse fish; pat dry. Cut fish into 4 portions. Lightly sprinkle with salt and pepper; place in shallow dish. In small mixing bowl stir together the vinegar, oil, garlic pepper, and 1/4 teaspoon salt. Pour 2 tablespoons of the vinegar mixture over fish. Cover and marinate at room temperature for 5 minutes. Drain fish, reserving marinade. Grill fish and onion slices on lightly greased rack of an uncovered grill directly over medium heat for 6 to 9 minutes or until fish flakes easily when tested with a fork, turning and brushing with reserved marinade after 4 minutes.

2. While the fish is cooking, in a large heavy skillet* toss together the tomatoes, spinach, and water. Place skillet on grill rack directly over medium heat. Cook 3 to 4 minutes or until spinach begins to wilt, stirring occasionally. Transfer spinach mixture to serving platter; place fish and onion slices atop. Drizzle with remaining vinegar mixture. Makes 4 servings.