Steps
1. In a small bowl, combine olive oil, lemon juice, oregano, garlic powder, salt, and pepper.
2. Place the chicken breast in a resealable plastic bag or shallow dish and pour the marinade over it. Seal or cover and refrigerate for at least 30 minutes.
3. Preheat the grill or a grill pan over medium-high heat.
4. Remove the chicken from the marinade and discard the leftover marinade.
5. Grill the chicken for about 6-7 minutes on each side, or until it reaches an internal temperature of 165°F (75°C).
6. Let the chicken rest for a few minutes before serving. Garnish with a lemon slice and fresh parsley.