In a bowl, combine the chicken cubes, barbecue sauce, olive oil, garlic powder, onion powder, smoked paprika, salt, and pepper. Toss to coat the chicken evenly. Marinate for at least 30 minutes in the refrigerator for best flavor.
Preheat the grill or a grill pan over medium-high heat. Thread the marinated chicken onto skewers.
Grill the chicken skewers for about 10-12 minutes, turning occasionally, until the chicken is cooked through and has nice grill marks. The internal temperature should reach 165°F.
While the chicken is grilling, prepare the salad by combining the mixed greens, cherry tomatoes, cucumber, red onion, and corn in a large bowl.
Once the chicken is done, remove it from the skewers and let it cool slightly. Add the chicken to the salad and toss gently to combine.
Drizzle additional barbecue sauce over the salad and sprinkle with cheddar cheese if desired. Garnish with fresh cilantro or parsley before serving.