1Heat gas or charcoal grill. In small bowl, mix all dressing ingredients. Cover; refrigerate until serving. Cook corn as directed on bag. Rinse with cold water; drain and set aside.
2In medium bowl, mix butter and 1 teaspoon blackened fish seasoning. Add shrimp; toss to coat. Place shrimp on grill over medium heat. Cover grill; cook 5 to 6 minutes, turning once and brushing with any remaining butter mixture, until shrimp are pink.
3On serving platter or 4 plates, arrange salad greens. Top with bell pepper, avocado, corn and croutons. Arrange shrimp on top. Serve with dressing.