Preheat a grill until it is hot, around 400-450 F. While the grill is preheating, season the pork chops with the garlic powder and kosher salt on both sides.
Place them onto the grill and cook them for several minutes on the first side. Flip them to the other side and cook for another few minutes. Then flip them again but turn them 90 degrees to make a crosshatch pattern. Then repeat on the other side. The total cooking time should be around 5-7 minutes, depending on your grill. You will want to look for pork chops that are cooked through and have reached an internal temperature of at least 145 F.
While the pork chops are cooking, make the compound butter combining softened/room temperature butter, lemon zest and the fresh thyme leaves together. Add the kosher salt and mix well.