Cong Shao Hai Shen (葱烧海参) — Scallion-Braised Sea Cucumber

Ingredients

• 4–6 dried sea cucumber, whole; to yield approximately 400–500 g rehydrated
• For the scallion braise
• 100 g large scallion (da cong), cut into 5 cm pieces
• generous neutral oil, sufficient to deep-fry and caramelise the scallion
• 200 ml superior stock (qing tang), the best available
• 2 tbsp Shaoxing wine
• 2 tbsp light soy sauce
• 1 tbsp oyster sauce
• 1 tsp dark soy sauce
• 1 tsp sugar
• To finish
• 1 tbsp cornstarch, mixed with cold water to form a slurry

Method

1. 1
   Day 1 — Place the dried sea cucumbers in a container of cold water. Leave to soak for 24 hours. They will begin to soften. The flesh should yield slightly to pressure by the end of the period.
2. 2
   Day 2 — Transfer the sea cucumbers and fresh cold water to a covered pot. Bring to a boil, turn off the heat, and allow to cool slowly, undisturbed. Repeat this boil-and-cool cycle once more on the same day. The bodies will expand further and the exterior will become visibly smoother.
3. 3
   Day 3 — The sea cucumbers should now be pliable and substantially expanded. Using a knife, cut each one open along its length and remove the internal organs and any calcified ring. Rinse thoroughly under cold running water. Repeat the boil-and-cool process once. The flesh should feel supple and spring back gently when pressed.
4. 4
   Day 4 — The sea cucumbers are fully rehydrated. They should measure 4–5 times the volume of the dried original and be uniformly silky to the touch with no rubbery resistance. Any piece that remains firm at its centre must be returned to a further boil-and-cool cycle before proceeding. This rehydration is the foundation upon which the entire dish rests: an insufficiently rehydrated sea cucumber will neither absorb the braising sauce nor achieve the required texture — this is where the dish lives or dies.
5. 5
   Set a wok or wide braising vessel over medium-low heat and add a generous quantity of neutral oil. Add the scallion pieces (da cong, cut into 5 cm lengths) and fry slowly for 10–15 minutes, turning occasionally. The scallion will collapse, deepen in colour to a rich amber-brown, and exhale a sweet, caramelised fragrance — this scallion oil is the cooking medium and the essence of the cong shao technique.
6. 6
   Add the superior stock (qing tang), Shaoxing wine, light soy sauce, oyster sauce, dark soy sauce, and sugar to the scallion oil in the wok. Stir to combine. Lower the rehydrated sea cucumbers into the liquid. Reduce the heat to low and braise, covered, for 30–45 minutes. The cucumbers will swell further and darken as they absorb the sauce; they should feel yielding but intact when pressed with a spoon.
7. 7
   Remove the sea cucumbers and set aside. Raise the heat and reduce the braising liquid until it thickens to a near-glaze, concentrating the scallion and soy flavours. Return the sea cucumbers to the pan. Add the cornstarch slurry in a thin stream, stirring constantly, until the sauce coats the cucumbers in a glossy, clinging film. The surface should be visibly lacquered and catch the light.