Blend dressing ingredients in blender or food processor until smooth. I cook the shrimp after peeling and deveining them by pan frying them for a few minutes in Italian dressing. Combine corn, black beans, zucchini, avocado, red pepper and red onion in large bowl. Reserve 6 or more shrimp for garnish. Cut remaining shrimp crosswise into 1/2 inch thick rounds, add to salad. Toss salad with dressing. Cover and refrigerate for at least 1 hour. Arrange lettuce leaves on plates or in a large dish. Top with salad. Garnish with whole shrimp, cilantro sprigs and lime wedges.