In a large bowl, combine the romaine lettuce, cherry tomatoes, cucumber, bell pepper, corn, black beans, avocado, red onion, and cilantro. Toss gently to mix the ingredients evenly.
In a separate small bowl, whisk together the lime juice, olive oil, chili powder, salt, and pepper until well combined.
Pour the dressing over the salad and toss again to coat all the ingredients evenly.
Sprinkle the shredded cheese on top before serving.
Serve immediately or refrigerate for up to 30 minutes to allow the flavors to meld.