Dust the angelfish fillets with a little flour, salt and pepper, then shallow-fry in vegetable oil until nicely browned and just cooked. Set aside.

Peel and halve the onions, then slice thinly across the grain.

Combine the spices, vinegar, sugar and water in a large saucepan. Add the onion and bay or lemon leaves and bring to a boil. 

Turn down the heat and simmer for 20 to 30 minutes, or until the onions are tender but still with a bit of bite. Taste to check the sweet-sour balance.

Flake the fish into large pieces, then layer with the spice and vinegar mixture and sultanas in a large glass jar or ceramic container, tightly packing the fish and dividing the liquid and onion so that there’s enough to sufficiently cover each layer.

Cover and leave to cool. Chill for at least 2 days before serving.

Cook’s note: To make the hanepoot sambal, mix sliced hanepoot grapes with fresh coriander leaves, then drizzle with lemon juice and top with finely chopped chilli.