Preheat your oven to 400°F (200°C).
In a small bowl, whisk together olive oil, lemon juice, garlic powder, onion powder, oregano, thyme, salt, and black pepper until well combined.
Place the chicken breasts in a large baking dish and pour the marinade over them, ensuring they are well coated. Let them marinate for at least 15 minutes (or up to 2 hours in the refrigerator for more flavor).
Arrange the marinated chicken breasts in a single layer in the baking dish. Top with lemon slices.
Bake in the preheated oven for 25-30 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C).
Remove from the oven and let the chicken rest for 5 minutes before slicing. Garnish with chopped parsley and additional lemon slices if desired.