Pound chicken breasts to 1/2 inch thickness with a mallet. (This step is optional, but will help the marinade penetrate more deeply and reduce cooking time).

Add Greek dressing, sea salt and chicken breasts to a zip-top bag. Seal and marinate 20 minutes. For best results, marinate overnight.

Preheat oven to 375 F. Heat a cast iron skillet over medium-high heat and add the oil. When shimmering, add the chicken breasts (do not crowd the pan).

Cook 2-3 minutes to golden, then flip.

Transfer the pan to the oven and cook for another 20 minutes or until internal temperature reaches 165 F.