Preheat your oven to 400°F (200°C) and line a small baking sheet with parchment paper.
Pat the chicken thighs dry with a paper towel and place them in a mixing bowl.
Add the olive oil, chili powder, cumin, garlic powder, sea salt, and black pepper to the chicken, tossing until evenly coated.
Arrange the chicken on the prepared baking sheet and bake for 20 to 22 minutes, or until the internal temperature reaches 165°F.
While the chicken bakes, chop the romaine lettuce, halve the cherry tomatoes, dice the bell pepper, and thinly slice the red onion.
Remove the chicken from the oven and let it rest for 5 minutes before slicing into thin strips.
Assemble the salad by placing the lettuce in a large bowl and topping it with the tomatoes, peppers, onions, and sliced chicken.
Finish the dish by adding the avocado slices and fresh cilantro, then squeeze the juice of the entire lime over the top before serving.