Preheat a large non-stick grill pan over medium-high heat for about 5 minutes.

In a small bowl, mix together olive oil, chili powder, ground cumin, garlic powder, salt, and pepper until well combined.

Brush both sides of the chicken breasts with the spice mixture and let it sit for 5 minutes.

Grill the chicken for 6-7 minutes on each side until cooked through and juices run clear.

Let the grilled chicken rest for 5 minutes on a cutting board, then slice into strips.

In a large bowl, combine black beans, corn, red bell pepper, avocado, red onion, cilantro, romaine lettuce, and cherry tomatoes.

Whisk Greek yogurt and lime juice in a small bowl, then season with salt and pepper to taste.

Drizzle the dressing over the salad and toss gently until well coated.

Top the salad with grilled chicken and shredded cheddar cheese, adding jalapeño if desired.

Serve immediately or store components separately for meal prep.