Crispy fish fillets in a tangy sweet-and-sour sauce are served over steamed rice. This protein-rich family bowl balances flavors beautifully and is a favorite with children.
Cut the fish fillets into bite-sized pieces and pat dry with paper towels.
Set up a breading station: in one bowl beat the egg, in another combine flour and 1/4 cup cornstarch, and in a third place remaining cornstarch.
Dredge the fish pieces first in flour mixture, then egg, then coat with cornstarch for extra crispiness.
Heat neutral oil in a large nonstick pan over medium-high heat. Fry the coated fish pieces in batches 2–3 minutes per side until golden and crisp. Drain on paper towels.
In another large pan, add a splash of oil, then sauté onion and bell pepper over medium heat for 3 minutes until slightly softened. Add pineapple chunks, stirring briefly.
In a bowl, mix together soy sauce, ketchup, rice vinegar, sugar, salt, and pepper. Pour into the pan with vegetables and bring to a gentle simmer.
Add the fried fish pieces to the sauce. Simmer very gently for 1–2 minutes until just coated and heated through; avoid breaking the crispy coating.
Place steamed rice into serving bowls. Spoon sweet and sour fish with sauce and vegetables over the top and serve immediately.