1. Heat a grill pan over medium-high heat. Coat pan with cooking spray. Sprinkle fish evenly with salt and pepper. Add fish to pan; cook 2 minutes on each side or until desired degree of doneness. Transfer to a cutting board.
2. Combine cabbage and next 4 ingredients (through orange) in a large bowl. Combine sugar and remaining ingredients in a small bowl, stirring well with a whisk. Reserve 1 tablespoon dressing. Drizzle remaining dressing over salad; toss gently to coat. Divide salad mixture evenly between 2 plates. Cut each tuna steak across the grain into 1/4-inch slices; arrange over salad mixture. Drizzle 1 1/2 teaspoons reserved dressing over each serving.
For dessert: Spoon 1/2 cup coconut sorbet into each of 2 dessert bowls; top each serving with 2 tablespoons diced peeled mango and 1 tablespoon toasted flaked sweetened coconut.
MyRecipes is working with Let's Move!, the Partnership for a Healthier America, and USDA's MyPlate to give anyone looking for healthier options access to a trove of recipes that will help them create healthy, tasty plates. For more information about creating a healthy plate, visit www.choosemyplate.gov.