Prepare the Marinade:
In a bowl or zip-top bag, whisk together olive oil, lemon juice, garlic, smoked paprika, oregano, onion powder, salt, and pepper.
Marinate the Chicken:
Add chicken to the marinade and toss to coat well. Cover and refrigerate for at least 30 minutes or up to 8 hours for deeper flavor.
Preheat the Grill:
Heat a grill or grill pan over medium-high heat. Lightly oil the grates to prevent sticking.
Grill the Chicken:
Remove chicken from marinade and grill for 5–7 minutes per side, depending on thickness, or until internal temperature reaches 165°F (74°C) and juices run clear. Flip only once to get great grill marks.
Rest and Serve:
Let chicken rest for 5 minutes before slicing. Serve with your favorite sides, over salads, or in wraps.