Marinate Tuna for an hour in the refrigerator. Preheat the grill. Grill the Tuna on high for 2 to 3 minutes on each side. Lower the heat and cook until Tuna reaches the desired doneness. Remove the Tuna and allow to cool slightly. Slice, then toss with yogurt, Mayonnaise, Onion, lemon,garlic,relish, and tomatoes. Serve open0faced on toasted bread or with salad greens. Nutritional Information Calories 300, Protein 39g, Fat 6 g, Sat Fat 1.5g, Cholesterol 23mg, Fiber 1g, Sodium 470mg Temperature: grill high, then low From the cookbook of George Hirsch "Living It Up"