Heat coconut oil in a wok or large pan over medium heat. Add the onions, garlic, dried chillies, and the curry leaves. Stir for a minute until fragrant, then toss in the coriander, mustard seeds and turmeric.

Once fragrant, mix in the tomato paste, stirring to combine and deepen the flavours. Add in the cherry tomatoes, and toss for another minute before pouring in the coconut milk and stock. Stir well, bringing the sauce to a simmer.

Bring to a simmer, then add the fish into the pan. Let it bubble away briefly. Stir in the tamarind, some salt and let simmer until the fish is cooked through.

Serve the curry over bowls of steamed basmati rice, scattering with coriander leaves.