01 - In a medium mixing bowl, whisk together the olive oil, lemon juice, minced garlic, smoked paprika, dried oregano, kosher salt, black pepper, and chili flakes until well combined.
02 - Place the chicken breasts in a large resealable plastic bag or shallow dish. Pour the marinade over the chicken, turning each piece to coat evenly on all sides. Seal tightly and refrigerate for at least 1 hour, ideally up to 4 hours for maximum flavor penetration.
03 - Preheat an outdoor grill or grill pan to medium-high heat (approximately 400°F). Lightly brush the grates with oil to prevent sticking.
04 - Remove the chicken from the marinade, allowing any excess to drip off. Place the breasts onto the hot grill and cook for 6 to 8 minutes per side, until a meat thermometer inserted into the thickest portion registers 165°F and the juices run clear.
05 - Transfer the grilled chicken to a clean plate or cutting board and let it rest for 5 minutes. This allows the juices to redistribute throughout the meat for optimal tenderness.
06 - Slice or serve the chicken breasts whole, garnished with freshly chopped parsley and lemon wedges alongside.