Combine 5.1 g lemon juice, 0.3 g salt and the marinade spice in a wide dish. Coat 600 g fish thoroughly with this mixture, cover and leave in the refrigerator for 30 minutes.
Soak the dried chillies for the paste in 250 ml of water for 15 minutes, then drain, keeping 30 ml (2 tbsp) of the soaking liquid. In a food processor, blend the soaked chillies, the reserved liquid, the spices for the paste, 80 g fresh coconut, 150 g chopped onion, 1.5 teaspoon garlic and 5.2 g tamarind extract into a completely smooth paste.
Heat 27 g vegetable oil in a wide, shallow pan set over medium heat. Fry 150 g sliced onion for 7 to 8 minutes until softened. Stir in the prepared spice paste and cook for 6 to 7 minutes until golden brown, splashing in a small amount of water if it begins sticking to the bottom.
Pour 1 litre of water into the pan and simmer for several minutes until oil surfaces. Stir in 120 g puréed tomato, 18 g green chilli, okra to taste and salt to taste. Simmer for 6 minutes, add the marinated fish, and cook gently for 4 to 5 minutes until the fish is just cooked through. Garnish with chopped coriander leaf to taste.
Use 80% of the weight, finely shredded and browned slowly with a pinch of asafoetida. Replicates the bulk and natural sweetness in gravies without allium.
Use 40% to 50% of the fresh tomato weight mixed with a splash of water. Imparts a deeper red colour, thicker sauce, and slightly sweeter cooked flavour.
Steep a tiny pinch (0.1 g per 2 g turmeric) in 2 tbsp warm water; use to match the rich golden hue. Contributes an aristocratic, honeyed floral flavour rather than earthy bitterness.
Use 50% to 60% of the weight, soaked in equal parts warm water for 15 minutes before grinding. Works well for chutneys, though texture is slightly finer and sweeter.
Use 1.2 times the weight in curries. Adds creamy richness and authentic flavour, but makes gravies smoother and eliminates the grated, chewy mouthfeel.
Use 15% to 20% of the weight (about 1 g for every 5 to 6 g fresh cloves). Whisk into sauces; gives a savoury, toasted garlic flavour without raw pungency.