Preheat your oven to 400°F (200°C) and line a small baking sheet with parchment paper.
In a small mixing bowl, whisk together 0.25 tablespoons of avocado oil, the lemon juice, dried oregano, garlic powder, sea salt, and black pepper to create the marinade.
Place the chicken breast on the prepared baking sheet and brush the marinade evenly over both sides.
Roast the chicken in the oven for 20 to 25 minutes, or until the internal temperature reaches 165°F (74°C).
While the chicken is roasting, heat the remaining 0.5 tablespoons of avocado oil in a large skillet over medium heat.
Add the broccoli florets and sliced bell peppers to the skillet and sauté for 6 to 8 minutes until they are tender-crisp and slightly caramelized.
Warm the pre-cooked quinoa in a small saucepan or the microwave until heated through.
Allow the chicken to rest for 5 minutes after roasting, then slice it into strips.
Serve the sliced chicken over the bed of quinoa alongside the sautéed vegetables.