Preheat your oven to 400°F.
In a small bowl, combine lemon juice, minced garlic, and olive oil. Then season with a pinch of salt and pepper if desired.
Place the chicken breast on a baking tray and brush with the lemon garlic mixture, ensuring even coating.
Roast the chicken in the oven for 20-25 minutes or until the internal temperature reaches 165°F.
While the chicken is roasting, cook quinoa according to package instructions.
Heat a non-stick skillet over medium-high heat. Add sliced red bell pepper, zucchini, and red onion, and sauté until the vegetables become slightly crispy and tender, about 5-7 minutes.
To assemble, layer the quinoa in a bowl, top with the roasted chicken sliced into strips, and add the crispy vegetables.
Drizzle a little extra lemon juice or olive oil if desired, then serve immediately.