Sear the Chicken: Pat the chicken thigh pieces dry with a paper towel and season them generously with salt and pepper. Heat the oil in a large, heavy-bottomed frying pan or skillet over a medium-high heat. Add the chicken in a single layer (work in batches if necessary to avoid overcrowding) and cook for 5-7 minutes, turning occasionally, until it's golden brown on all sides. Remove the chicken with a slotted spoon and set it aside on a plate.

Sauté the Aromatics: Reduce the heat to medium. Add the chopped onion to the same pan and cook for about 5 minutes, stirring occasionally, until softened and translucent. Add the minced garlic, grated ginger, and sliced chillies, and cook for another minute until fragrant.

Bloom the Spices: Stir in the smoked paprika, turmeric, and cumin. Cook for 30-60 seconds, stirring constantly, until the spices release their aroma. This little step of toasting the spices makes a huge difference to the final flavour.

Create the Sauce Base: Add the tomato purée and stir it into the onion and spice mixture. Cook for one minute, then pour in the chicken stock to deglaze the pan, scraping up any browned bits from the bottom with a wooden spoon.

Simmer the Sauce: Pour in the full-fat coconut milk and stir everything together until smooth. Bring the sauce to a gentle simmer, then reduce the heat to low.

Cook the Chicken: Return the browned chicken (and any juices from the plate) to the pan. Stir to coat, then cover the pan with a lid and let it simmer gently for 15-20 minutes, or until the chicken is cooked through and tender, and the sauce has thickened slightly. What works best for me is keeping the heat low to ensure the chicken stays juicy.

Finish and Serve: Turn off the heat. Stir in the lime zest, lime juice, and most of the chopped fresh coriander. Have a taste and adjust the seasoning with more salt, pepper, or lime juice if needed. Serve immediately, garnished with the remaining coriander.