Tom Nuong Sa

Tom nuong sa belongs to the seafood-grill tradition of Vietnam's central coast — Hue, Hoi An, Da Nang, Nha Trang — where evening grills are set up on the beach or along the lagoons. The pairing of prawn with lemongrass appears wherever lemongrass grows, but using the stalk itself as a skewer is a coastal technique that doubles the lemongrass exposure (mince in the marinade, plus stalk core releasing oil during grilling). The dish also appears at central-region weddings and as one course in a multi-prawn 「tom 5 mon」 (five-prawn-course) menu.

Central-coast (Hue, Hoi An, Da Nang, Nha Trang) lemongrass-skewered prawn. Shell stays on — it takes the char while the flesh inside steams in its own juice. Marinade capped at 20 minutes because nuoc mam is salty enough to denature shrimp protein and turn it mealy.

Shells are coral-orange streaked with black at the legs and tail, glossed with caramelized fish-sauce sugar; the lemongrass mince has crisped against the shell into fragrant flecks. First move: suck the head — the brain butter has mixed with the marinade. Then peel; the flesh is taut, sweet, with lemongrass perfume that has worked through the shell. Lime-pepper-salt at the table. The thinner the lemongrass mince, the deeper the perfume — coarsely chopped lemongrass falls off and burns.

Two tricks separate this from a generic grilled prawn. First, leaving the shell on traps moisture and concentrates flavour — the shell takes the char, the flesh stays juicy; peeled prawns dry out in 90 seconds on the same grill. Second, the marinade rest is capped at 20 minutes because nuoc mam is salty enough to denature prawn protein; longer and the texture turns mealy. The fine-minced lemongrass adheres to the shell during the rest; on the grill, the cellulose chars and the trapped oil migrates inward through the perforated back-shell into the flesh.