Chinese Sweet and Sour Fish Fillet Stir-fry

Method10 steps · about 45 min

1. 1

   Step 1: Pat the cod dry and cut it into 1-inch (2.5 cm) cubes. Dice the onion and bell peppers, and have all the sauce ingredients beside the stove before heating the oil (3 cups). Mix the 1½ tbsp sauce cornstarch with its separate 2 tbsp water and keep this slurry aside. Put the 3 cups canola oil in a suitable small, deep pot with ample space above the oil, and heat to 380°F (193°C), checking with a thermometer.

   Uses 340 g cod fillet (12 oz), patted dry and cut into 1-inch cubes · 3 cups canola oil for frying · ¼ cup red onion, cut into 1-inch dice · ¼ cup red bell pepper, cut into 1-inch dice · ¼ cup green bell pepper, cut into 1-inch dice · 1 1/2 tablespoons cornstarch (mixed into a slurry with 2 tablespoons water) · 2 tbsp water for the sauce slurry

2. 2

   Step 2: When ready to fry, mix the ¾ cup flour, ¼ tsp baking powder, 1 tbsp batter cornstarch, ½ tsp batter salt, ⅛ tsp turmeric and ⅛ tsp white pepper. Stir in ¼ tsp sesame oil and the cold ⅔ cup seltzer until the batter is smooth. Keep the prepared sauce slurry separate from this batter. A drop of batter should rise promptly and turn light golden rather than brown; adjust the heat before adding fish.

   Uses ¾ cup all-purpose flour · ¼ teaspoon baking powder · 1 tablespoon cornstarch · ½ teaspoon salt · ⅛ teaspoon turmeric powder · ⅛ teaspoon white pepper · ¼ teaspoon sesame oil · ⅔ cup cold seltzer water

   
3. 3

   Step 3: Coat a small batch of cod in batter, letting excess drip back into the batter bowl. Lower the pieces into the hot oil one by one without overcrowding. Fry for about 3–4 minutes, checking from 3 minutes, until golden brown and cooked through; the centre of the fish must reach 63°C (145°F). Continue as needed to reach the cooked centre, adjusting the heat so the coating does not brown before the fish is cooked.

   Check the first fish batch from 3 minutes · 3 minUses A small batch of the dry cubed cod from step 1, leaving the remaining raw fish separate · The batter needed to coat this first batch from step 2; unused batter remains separate · The 3-cup frying reservoir heated in step 1, excluding its other prepared outputs

   
4. 4

   Step 4: Lift the cooked fish onto a wire rack over a tray to drain. Repeat the battering and 3–4-minute frying procedure with all the remaining cod in small batches, checking each batch is cooked through to 63°C (145°F). Let the oil return to frying temperature between batches. Retain the used oil in its pot for the sauce draw and possible final crisping, and discard the spent raw-fish batter when all the fish is cooked.

   Uses The cooked first batch from step 3, lifted out of its oil · The retained oil from step 3, separate from the lifted fish · Further small batches of the remaining prepared cod from step 1 · Further coating draws from the same batter mixed in step 2

   
5. 5

   Step 5: Heat a wok or separate pan over medium-high heat. Draw 2 tsp oil from the used frying reservoir into this pan, then add all the prepared onion and bell peppers. Stir-fry for 30 seconds.

   Stir-fry the onion and peppers · 1 minUses 2 tsp drawn from the actual used frying reservoir retained in step 4; the rest stays in its pot · All ¼ cup onion, ¼ cup red bell pepper and ¼ cup green bell pepper diced in step 1, excluding its other outputs

   
6. 6

   Step 6: Add the 1 tbsp ketchup and stir-fry with the vegetables for another 20 seconds.

   Fry the ketchup with the vegetables · 1 minUses All vegetables and their 2 tsp oil from step 5 · 1 tablespoon ketchup

7. 7

   Step 7: Add the ¾ cup pineapple chunks, ¾ cup pineapple juice, 2½ tbsp red wine vinegar, ⅓ cup sauce water, ¼ tsp sauce salt and 2 tbsp sugar. Bring to a simmer, lower the heat and simmer for 2 minutes.

   Simmer the sweet-and-sour sauce · 2 minUses All vegetables, ketchup and sauce oil from step 6 · ¾ cup canned pineapple chunks · ¾ cup pineapple juice from the can · 2½ tbsp red wine vinegar · ⅓ cup water for the sauce · ¼ teaspoon salt · 2 tablespoons sugar

   
8. 8

   Step 8: Stir the separate sauce slurry again, then add it gradually only as needed, stirring until the hot sauce coats the back of a spoon. Keep any unused slurry separate. Leave the sauce ready while checking whether the fried fish needs crisping.

   Uses All sauce from step 7 · An as-needed draw of the separate 1½ tbsp cornstarch and 2 tbsp water slurry mixed in step 1

   
9. 9

   Step 9: If the cooked fish has softened, heat the remaining frying oil to 400°F (204°C) and refry the fish for about 30 seconds per batch to crisp it, without overcrowding; drain again on the rack. Keep the fish out of the oil if it is already crisp. Either route leaves fully cooked, drained fish ready to fold into the sauce, with the oil kept separate.

   Optional first fish-crisping batch · 1 minUses All drained cooked fish from step 4, separate from the retained frying oil · The remaining actual frying oil from step 4 after its 2 tsp sauce draw in step 5

10. 10

    Step 10: Add the drained cooked fish to the thickened sauce. Fold gently with three or four scooping motions until the pieces are coated without breaking the crisp coating. Serve immediately, sharing the fish and sauce between four portions.

    Uses All thickened sauce from step 8, excluding its unused slurry · All cooked fish passed through or optionally recrisped in step 9, lifted separately from its frying reservoir