Cook the chicken: Season chicken breasts with salt, pepper, cumin, and chili powder. Grill or bake until golden and fully cooked, then slice thinly.
Prepare the base: Add lettuce and greens to a large bowl.
Add toppings: Layer in black beans, corn, bell pepper, avocado, cherry tomatoes, red onion, and cheese.
Make the dressing: In a small bowl, whisk together olive oil, lime juice, Greek yogurt, chili powder, cumin, garlic powder, salt, and pepper.
Combine: Pour dressing over the salad and toss lightly to coat all ingredients.
Serve: Top with sliced chicken and garnish with cilantro. Serve chilled or at room temperature.