Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Rinse the quinoa under cold water, then combine it with 0.5 cup of water in a small pot. Bring to a boil, then reduce heat to low, cover, and simmer for 15 minutes until fluffy.
While the quinoa cooks, dice the zucchini and red bell pepper into bite-sized pieces.
Place the chicken breast and chopped vegetables on the prepared baking sheet. Drizzle with olive oil and season with sea salt, black pepper, garlic powder, and dried oregano.
Roast in the oven for 18 to 20 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender and slightly browned.
Remove from the oven and let the chicken rest for 5 minutes before slicing into thin strips.
In a large bowl, fluff the cooked quinoa with a fork and stir in the fresh lemon juice and chopped parsley.
Top the quinoa with the roasted vegetables and sliced chicken, then serve warm.