Preheat oven to 375oF (191oC) and line a baking sheet with parchment paper.
In a large bowl, toss the sliced bell peppers with the olive oil. Transfer to a baking sheet and add the sliced chicken breast. Sprinkle with cumin, chilli powder, salt and pepper.
Bake for 30 minutes, or until chicken is cooked through. Slice avocado and at on top!