Sweet and Sour Carp

Ingredients

• 3 lb Carp
• 40 g Tomato ketchup
• 20 g White sugar
• 10 g White vinegar
• 10 g Cornstarch
• 30 g Salt
• 30 g Spring onion
• 30 g Ginger
• 25 g Rice wine
• 1 sprig Coriander
• 50 g Water
• 100 g Flour
• 200 g Cornstarch (for batter)
• 180 g Water (for batter)
• 1 Egg
• 1 L Oil (for deep-frying)

Method

Scale and gut the carp, then fillet it by laying the fish belly-down and making vertical cuts 1 cm deep along the body at 3–4 cm intervals. This technique, called half-splitting or butterfly scoring, increases surface area for the batter to grip and allows heat to penetrate faster during deep-frying, shortening cooking time and preventing a dense interior. Score the thickest parts lightly across the middle to ensure even cooking.

The marinade removes the muddy, off-flavour compounds carp accumulates from its environment. Slice ginger and spring onion, then bruise them aggressively and squeeze their juices directly over the fish — this releases volatile compounds that mask fishiness better than leaving the aromatics whole. Add 20 g salt and 25 g rice wine, then massage the flesh for a full minute to open the muscle structure and allow the marinade to penetrate. Rest for at least 30 minutes; longer marinating (up to 2 hours) yields noticeably cleaner flavour.

For the batter, combine 100 g flour, 200 g cornstarch, 180 g water, and 5 g salt. Mix by hand until the consistency stretches in thin threads — this indicates the gluten network is developed enough to hold the coating without tearing. Beat in the egg. Let the batter rest 30 minutes so the starch fully hydrates; this creates a crispier crust with less oil absorption during frying. Pat the fish completely dry before coating; any moisture on the surface prevents adhesion.

Heat 1 litre of oil to 200–210 °C — check by dipping the fish's head first and basting the body with a spoon until the batter sets, then lower it fully into the oil. Use a spatula and skimmer to support the head and prevent sticking. After 3 minutes, flip carefully and fry a further 2–3 minutes until the batter turns deep golden and fish-and-seafood flesh flakes easily from the backbone. Transfer to a plate.

For the sauce, combine 50 g water, 40 g tomato ketchup, 20 g sugar, and 10 g vinegar; bring to a boil. Slurry 10 g cornstarch with 10 g water separately, then whisk it into the boiling sauce slowly — the heat cooks out the raw starch flavour, and the stirring prevents lumps. Stop after 20 seconds once the sauce coats the back of a spoon. Pour evenly over the fish and finish with fresh coriander. Serve immediately while the crust is still crisp.