The tuna steak in this fruit-accented dish stays moist and flavorful when cooked as quickly as possible. Pan-searing over high heat is ideal -- it seals the juices on the inside and gives the outside an irresistible caramel-colored crust.
For citrus relish, in a small bowl combine vinegar, soy sauce, and ginger. Whisk in the 1 tablespoon olive oil. Cut grapefruit sections into thirds and orange sections in half. Stir fruit pieces, red onion, and the 2 tablespoons cilantro into vinegar mixture. Set aside.
Rinse fish; pat dry. In a large skillet heat the 2 teaspoons olive oil over medium-high heat. Add fish and cook for 6 to 9 minutes or until fish flakes easily when tested with a fork, turning once. Sprinkle with salt and pepper. Serve the fish with citrus relish. If desired, garnish with cilantro sprigs. Makes 4 servings.