20 ounces fresh tuna steaks, 1 inch thick
3 tablespoons white wine
3 tablespoons olive oil
2 tablespoons red wine vinegar
1/2 teaspoon chopped fresh rosemary
1/2 teaspoon ground black pepper
1/8 teaspoon salt
1 clove garlic, minced
6 cups packed torn salad greens
1 cup halved cherry tomatoes
Preheat grill for medium heat.
Place tuna in a glass dish. Prepare the vinaigrette by whisking together the wine, olive oil, red wine vinegar, rosemary, pepper, salt and garlic. Pour 2 tablespoons over fish and turn to coat. Marinate 15 to 30 minutes, turning once. Reserve remaining vinaigrette for salad dressing.
Coat grill rack with cooking spray and place on grill to heat 1 minute. Place tuna on grill 4 to 6 inches over hot coals. Cover with lid or tent with foil. Cook, turning once, just until tuna begins to flake easily when tested with a fork, about 7 minutes. Discard marinade.
Arrange salad greens on 4 plates. Place hot tuna on greens and add cherry tomatoes. Stir remaining vinaigrette and drizzle over salads.