Finely mince the tender lower 3 to 4 inches of lemongrass to make about 3 tablespoons. Mix with garlic, shallot, fish sauce, soy sauce, sugar, oil, lime juice and pepper.
Coat chops with the marinade, cover and refrigerate for 30 minutes; the prep time includes this rest.
Heat an outdoor grill to about 400°F with a cooler indirect area and clean the grate. Lift chops from the marinade, let excess drip off and discard the used marinade.
Grill for 4 to 6 minutes per side until browned in patches and the thickest meat reaches at least 145°F, shifting to indirect heat if the edges darken too quickly.
Rest for at least 3 minutes and serve with the cooked lemongrass seasoning clinging to the meat.