Heat the oil in a large pan and cook the onion and butternut squash on a low heat for about 15 minutes. Add the tomatoes and cumin seeds, then cook for a further 5 minutes until the tomatoes are softened and pulpy.
Stir in the paprika, curry paste and stock and bring to the boil. Add the chicken and simmer gently for 15-20 minutes, covering with a lid half way through, until the chicken is cooked through. To check that the chicken is completely cooked, pierce a thick piece gently with a skewer - it's ready when the juices run clear.
Meanwhile, cook the rice according to the packet instructions.
Season the curry and add lemon juice to taste. Spoon into serving bowls with the drained rice and scatter with coriander leaves.
This dish is ideal for freezing so make double the quantity. Leave to cool completely before freezing and defrost thoroughly before gently reheating.
See more Curry recipes