Preheat grill to medium-high heat, approximately 400°F (200°C).

Pound chicken breasts to an even 3/4-inch thickness using a meat mallet to ensure uniform cooking.

In a small bowl, combine salt, black pepper, garlic powder, onion powder, oregano, and smoked paprika.

Brush both sides of the chicken with olive oil and apply the spice rub evenly.

Place chicken on the clean, oiled grill grates.

Grill for 5 to 6 minutes per side until the internal temperature reaches 165°F (74°C) as measured by an instant-read thermometer.

Remove chicken from the grill and transfer to a plate.

Let the meat rest for 5 minutes to allow juices to redistribute before serving.