Put the giant couscous in a pan and add the stock. Bring to the boil and then allow to simmer for 6 minutes. Drain the couscous
Put the tomato in a jug or large mug and add boiling water. Allow to stand for 2 minutes. Lift the tomato out and peel.
Chop up the coriander finely
Put the couscous in a salad bowl, add the chopped tomato and coriander. Mix well. Juice the lime over the mixture and stir just a little to distribute the flavour