1. Fill your kettle and boil it. Trim the roots and top 3cm off the leek. Halve it, rinse out any grit, then finely slice it. Set to one side.
2. Place a medium pan on a medium heat and add the cinnamon stick and star anise to the pan. Toast the spices in the dry pan for 2 mins till aromatic. Tip them out onto a plate and set aside.
3. Drizzle ½ tbsp oil into the pan and add the diced chicken breast. Turn the heat up to medium-high. Fry, turning the chicken pieces once or twice, for 6-8 mins till browned.
4. While the chicken fries, dice the tomatoes. When the chicken is browned, lift it out of the pan onto a plate, and set to one side. Add another ½ tbsp oil to the pan and add the leek. Season with a pinch of salt and pepper. Fry, stirring often, for 6-7 mins till the leek starts to soften and colour. If it starts to brown too quickly, add a splash of water and turn the heat down a little.
5. While the leek fries, peel and grate or finely chop the garlic and ginger. Halve the chilli, scrape out the seeds, and finely chop it. Finely chop the coriander stalks (keep the leaves for later).
6. Add the tomatoes, garlic, ginger, chilli and coriander stalks to the pan. Fry, stirring often, for 3 mins, till the tomatoes are soft and pulpy.
7. Return the chicken to the pan and add the cinnamon stick and star anise. Tip in the rice and stir everything together. Pour in 500ml boiling water, pop a lid on the pan and bring to the boil. Then turn the heat right down and simmer for 20 mins till the rice has absorbed the water, stirring once or twice. Turn the heat down if it gets too dry too quickly.
8. Take the pan off the heat and give the rice a stir. Taste and add a pinch more salt if you think it needs it. Divide the rice and chicken between 2 warm bowls, discarding the cinnamon stick and star anise if you spot them. Garnish with the coriander leaves to serve.