Ten Sune Gune (Sweet and Sour Fish)

Ingredients

• 2 pounds Sea bass, whole (Ask your fishmonger to gut and clean it whole for you if you are a beginner, keeping the fish intact.)
• 0 enough to cover fish in dish Water (for poaching fish) (Heat until almost boiling — around 90–95°C (195–205°F). Do not let it reach a full rolling boil.)
• 1 tablespoon Quong Sang Chong (water-chestnut flour) (Also labelled water chestnut starch or powder in Asian grocery stores. Used to thicken the sauce.)
• 1.5 cups Water (for sauce) (Plain cold or room-temperature water to form the base of the sauce.)
• 1 tablespoon Salt (Fine table salt works well here.)
• 1.5 tablespoons Sugar (Plain white granulated sugar.)
• 2.5 tablespoons Vinegar (The original recipe does not specify a type. White vinegar or rice vinegar both suit this dish.)

Instructions

1. 1If your fishmonger has not already done so, clean the sea bass: rinse it under cold running water, then carefully remove all the internal organs by making a small cut along the belly. Be gentle and work slowly to keep the fish completely whole — do not cut off the head or tail. Pat the fish dry with paper towels once cleaned.
2. 2Find a medium-deep dish (such as a deep baking dish or a large, deep-sided oven-safe serving dish) that is long enough to hold the whole fish flat. Place the cleaned fish into the dish.
3. 3Heat a kettle or large pot of water until it is almost boiling — you want it steaming and very hot (around 90–95°C / 195–205°F) but not at a vigorous boil. Carefully pour the hot water over the fish in the dish until the fish is well covered. Work slowly to avoid splashing.
4. 4Place a tight-fitting lid (or a sheet of foil pressed firmly over the top) on the dish. Set the dish on your stovetop over the lowest possible heat setting. The goal is to keep the water very hot throughout — it should barely tremble but must NOT come to a full boil. Leave the fish undisturbed for one full hour. Check occasionally to ensure the water is still hot; if it cools too much, briefly increase heat until steaming again, then reduce. This gentle method poaches the fish slowly so it stays tender.
5. 5About 10 minutes before the fish's hour is up, begin the sauce. Measure one tablespoon of Quong Sang Chong (water-chestnut flour) into a small bowl. Add a tiny splash of cold water — just a teaspoon or two — and stir or rub with the back of a spoon until completely smooth with no lumps. This is called making a slurry and ensures your sauce thickens evenly without clumping.
6. 6Pour one and a half cups of water into a small saucepan. Add one tablespoon of salt, one and a half tablespoons of sugar, and two and a half tablespoons of vinegar. Now add the smooth water-chestnut flour slurry from the previous step. Stir everything together well until the salt and sugar have dissolved.
7. 7Place the saucepan over medium heat. Stir the sauce constantly with a spoon — do not walk away — as it comes up to a boil. Once it begins to boil, keep stirring and cook for 1–2 minutes until the sauce turns slightly translucent and coats the back of the spoon. Remove from heat immediately. Constant stirring prevents the water-chestnut flour from settling and burning on the bottom of the pan.
8. 8Carefully lift the fish out of the poaching dish — use two wide spatulas or fish slicers to support it fully so it does not break. Transfer it to a clean, dry, warmed serving dish. Pour the hot thickened sauce evenly over the top of the whole fish. Serve immediately with steamed rice.