In a small bowl, whisk together the shallot, vinegars and olive oil; season with salt and pepper, to taste. Cut the tomatoes in halves or quarters (depending on size). In a large bowl, toss the tomatoes with 1/3 of the vinaigrette.
Arrange an assortment of tomatoes on each plate. Place the Mache in the same bowl and toss with the remaining vinaigrette; place on top of tomatoes. Shave Parmesan cheese over each salad. Taste and adjust seasonings.
Per Serving: 252 Calories (kcal); 23g Fat (5g Sat, 15g Mono, 2g Poly); 7g Protein; 7g Carbohydrate; 1g Dietary Fiber; 11mg Cholesterol; 545mg Sodium. Food Exchanges: 0 Grain (Starch); 1 Lean Meat; 1 Vegetable; 0 Fruit; 4 Fat; 0 Other Carbohydrates.