What cut of pork is best for thịt nướng? Pork shoulder is the standard choice. It has enough fat to stay tender under high heat and enough structure to hold its shape when sliced thin. Pork belly works too and produces a richer result. Pork loin is too lean and dries out quickly on a hot grill.
How thin should the pork be sliced? Four to five millimeters. Thinner than that and the pork overcooks before the char develops. Thicker than that and the exterior chars before the center cooks through. A sharp knife and cold pork from the refrigerator makes clean slicing easier.
Can I make this without a grill? Yes. A cast iron pan over high heat produces comparable results. The pan must be smoking hot before the pork goes in. Do not crowd the pan. Cook in batches if needed. Crowding drops the pan temperature and the pork steams instead of chars.
How long can the pork be marinated? Forty-five minutes is the minimum. Two hours produces noticeably better caramelization. Overnight in the refrigerator is the best option for maximum flavor penetration. Do not marinate longer than 24 hours as the fish sauce begins to break down the texture of the pork.
Can the grilled pork be made ahead? Yes. Grill the pork and refrigerate for up to 2 days. Reheat in a hot pan for 60 seconds per side before assembling. Do not microwave. It steams the pork and eliminates the char.
Should I add scallion oil to this sandwich? It is optional but worth trying. Mỡ hành, Vietnamese scallion oil, is a common finishing touch on grilled meat bánh mì in southern Vietnam. A tablespoon spooned over the grilled pork just before closing the sandwich adds fragrance and a thin layer of richness that works well with the char. The full recipe is on the Scallion Oil page.