Place chicken breasts in a large zip-top bag (or between two sheets of parchment). Pound them to an even ½-inch thickness using a rolling pin or meat mallet. This helps them cook evenly and stay juicy.

In a small bowl, mix olive oil, minced garlic, lemon juice, Italian seasoning, sugar, garlic powder, salt, and pepper. Pour the marinade into the bag with the chicken. Seal the bag and massage the marinade into the meat.

Let it marinate in the fridge for 4 to 12 hours, placed in a shallow dish. This step ensures the flavor seeps deep into the chicken.

Take the marinated chicken out of the fridge and allow it to sit at room temperature for about 20 minutes. Meanwhile, preheat your grill to high heat (around 400–450°F). Lightly oil the grates to prevent sticking.

Grill the chicken breasts 2–4 minutes per side, covered, until the juices run clear and the internal temperature reads 165°F (75°C).

Remove the chicken from the grill and let it rest for 5 minutes to allow juices to redistribute. Slice and serve!