In a shallow bowl whisk together vinegar, shallots, olive oil, pepper, lemon juice and zest. Thread meat on skewers and add to marinade; set aside for 1 hour. Grill skewers on a preheated grill, a few minutes per side. Serve 3 per person, garnished with salad greens and a spoonful of vinaigrette.
Yield: 4 servings