Make vinaigrette: In a small bowl whisk together vinegar, soy sauce, pepper, and salt to taste and add oil in a stream, whisking until emulsified. Vinaigrette may be made 1 day ahead and chilled, covered. Bring vinaigrette to room temperature and whisk before proceeding.
In a bowl toss mesclun with vinaigrette and divide among 8 salad plates.
vinaigrette recipe courtesy of Gourmet Magazine