Marinate the Chicken: In a bowl, whisk together olive oil, lemon juice, oregano, garlic powder, salt, and pepper. Add chicken breasts, coating them well. Cover and refrigerate for at least 30 minutes.
Preheat the Oven: Preheat your oven to 400°F (200°C).
Prepare the Asparagus: On a baking sheet, toss the trimmed asparagus with olive oil, salt, and pepper. Spread evenly.
Roast the Chicken: Place marinated chicken breasts on another baking sheet. Roast both the asparagus and chicken in the oven for about 20-25 minutes, or until the chicken reaches an internal temperature of 165°F (74°C) and the asparagus is tender.
Serve: Remove from the oven and let the chicken rest for a few minutes. Serve with roasted asparagus and garnish with lemon zest and fresh parsley, if desired.
