Make Ahead Tip: To make ahead: The greens and fruit can be tossed together (without the dressing) and stored under a barely moistened paper towel in the refrigerator for up to 3 hours.
If you prefer your tuna medium-rare, as it is often served in restaurants, use sushi-grade (or sashimi) tuna, if you can find it, and cook it for about 3 minutes per side.
To peel and slice a mango: Slice off both ends, revealing the long, slender seed inside. Set the fruit upright on a work surface and remove the skin with a sharp knife. With the seed perpendicular to you, slice the fruit from both sides of the seed, yielding two large pieces. Turn the seed parallel to you and slice the two smaller pieces of fruit from each side. Cut the fruit into slices.
People with celiac disease or gluten-sensitivity should use soy sauces that are labeled "gluten-free," as soy sauce may contain wheat or other gluten-containing sweeteners and flavors.
2 fruit, 1 vegetable, 4 lean protein, 3 1/2 fat