Season corn with salt and pepper to taste. Cook the corn by grilling for about 8-10 minutes over medium heat, rotating throughout) Cut corn off the cob and set aside.Combine all dressing ingredients in a food processor or blender and pulse until smooth.Combine lettuce, corn, black beans, bell peppers, avocados, and quinoa in a large bowl and toss to combine. Serve with dressing and garnish with lime wedges and additional cilantro if desired.