1. Rinse the rice under cold water, then tip it into a small pan. Use the side of a knife to slightly crush the cardamom pods and add to the rice. Pour in 300ml boiling water and add a pinch of salt. Pop on a lid, bring to the boil, then turn the heat right down under the pan. Gently simmer the rice for 8-10 mins till all the water has been absorbed, then take off the heat and let it sit in the pan for 5 mins to steam and finish cooking.
2. Meanwhile, peel the onions and thinly slice them. Peel the garlic and ginger and finely chop or grate both. Halve the chilli, scraping out the seeds and membrane for less heat, and finely chop.
3. Pour 1 tbsp oil into a large pan and warm to a high heat. Sprinkle the chicken breasts with a pinch of salt and pepper. Add the chicken to the pan and fry for 3 mins, till golden. Turn over and cook for a further 3 mins. Scoop the browned chicken out of the pan and transfer to a plate.
4. While the chicken is browning, cut the tomatoes into small chunks.
5. Return the empty pan used to brown the chicken back to a medium heat and add 1 tbsp oil. if needed. Slide in the chopped onions and stir fry for 4-5 mins, till slightly softened and caramelised. Stir in the chopped garlic, ginger and chilli. Add 1 tbsp garam masala and a pinch of salt and pepper. Cook for 1 min.
6. Tip the chopped tomatoes into the onions. Crumble in the coconut cream. Pour in 100ml boiling water. Stir well. Nestle the chicken fillets back into the sauce. Bring to the boil, then reduce to a simmer. Pop on a lid and cook for 5 mins.
7. Once the chicken and sauce has simmered for 5 mins, turn the chicken breasts over and simmer for a further 5 mins.
8. Use a slotted spoon to transfer the chicken breasts to a board. Slice into bite-size pieces and stir back into the sauce. If the chicken still isn’t quite cooked at this point, cook for a further 4-5 mins, till the meat is white all the way through.
9. Stir the butter through the sauce till combined. Divide the curry between bowls and serve with fluffy cardamom infused basmati rice on the side.