In a medium bowl, combine strawberries, orange sections, radishes, green onions, lemon juice, and sugar. Let stand at room temperature for 10 to 15 minutes to allow flavors to blend.
In a large bowl, toss the mesclun with the No-Fat Lemon Vinaigrette. If desired, season to taste with salt and pepper. Arrange mesclun mixture on a serving platter. Spoon strawberry mixture on top of mesclun mixture.
No-Fat Lemon Vinaigrette
In a small stainless-steel saucepan, combine shallots, white wine, sugar, rice vinegar, and garlic. Stir in 1 teaspoon cornstarch.
Cook and stir until mixture is slightly thickened and bubbly. Cook and stir for 1 minute more; cool. Stir in finely shredded lemon peel and lemon juice.