Nem cua bể: Hải Phòng Square Crab Spring Rolls

Keep the live crabs chilled until cooking; choose active crabs and discard any that are already dead. Steam the 900 g crabs over 250 ml water until the shells turn red-orange and the meat is opaque, about 15 minutes depending on size. Check that the thickest crab meat reaches 63°C. Cool just enough to handle, pick about 200 g meat and roe, cover and refrigerate while you prepare the filling.

Soak the glass noodles in warm water for 10 minutes and the dried mushrooms in hot water for 20 minutes. Drain everything thoroughly. Cut the noodles into 3 cm lengths; remove the shiitake stems and finely slice both mushrooms. Grate the carrot and squeeze it dry; roughly chop and squeeze the bean sprouts. Mince the onion, scallion and cilantro.

Mix the ground pork, chopped shrimp, noodles, mushrooms, carrot, sprouts, onion, scallion and cilantro with the egg, 15 ml fish sauce, 3 g salt and 2 g black pepper until evenly combined. Fold in the chilled crab meat and roe gently so visible pieces remain. Keep the filling refrigerated while you set up the wrappers and frying station.

Lay one rice-paper wrapper on a clean board and lightly wipe both sides with a little of the 60 ml beer or water; do not soak it. Place one-twelfth of the filling just below the centre and shape it into a compact square about 7 cm wide. Fold the lower edge over, fold in the sides and roll once to close. Brush the seam with egg white. Wrap the parcel in a second lightly moistened rice-paper sheet, folding it into the same square. Repeat to make 12 rolls. Rest seam-side down for 15 minutes so the wrappers adhere and lose surface tack.

Heat the 1.5 L frying oil in a deep heavy pot to 160°C, monitoring it with a clip-on thermometer. Fry the rolls in uncrowded batches for about 7–10 minutes, turning so each side cooks evenly. The first fry must bring the centre of the thickest filling to 71°C. Transfer the rolls to a wire rack and rest for at least 10 minutes. If not serving soon, cool and refrigerate within 2 hours; keep below 4°C.

Just before serving, raise the oil to 180°C. Fry the rolls again in batches for 90 seconds to 2 minutes, until deep golden and crisp. Drain on a clean rack. Keep the oil temperature steady and do not leave the pot unattended.

Prepare the rice vermicelli according to its package directions, drain and divide among four plates. Stir the 25 g sugar into 150 ml warm water until dissolved; mix in 40 ml fish sauce, 50 ml lime juice and the minced garlic, then add the sliced chili if using. Serve the rolls with lettuce, fresh mint and cilantro, noodles and dipping sauce. Cut each hot square in half at the table if desired.

Refrigerate leftover filling or cooked rolls in shallow covered containers within 2 hours, at or below 4°C. Use cooked crab and seafood within 2 days. Reheat cooked rolls in a 180°C oven until steaming hot throughout, or refry briefly; do not reheat at room temperature. Discard food left out for more than 2 hours.