Yucatan Lime Soup

Heat the oil in a large fireproof casserole. Add the onion, garlic, oregano, salt and chicken (if using) and cook over a moderately low heat until the onion is transparent.

Meanwhile, cut the carrots in half lengthwise, then into 1/4 inch slices. Add the carrots, beans and tomatoes to the casserole. Pour in the heated stock and the bunch of coriander and simmer for about 20 minutes.

Remove the chicken breasts from the casserole with a slotted spoon and set aside until cool enough to handle. Shred by hand into thin strips. Set aside.

Add the chili powder and lime slices and juice to the stock. Simmer for further 5 minutes over a moderate to low heat. Remove the bunch of coriander. Correct the seasoning if necessary, add the shredded chicken and simmer for another 5 minutes.

To serve, ladle the soup into individual bowls and garnish with the diced avocado and coriander. If you prefer a milder, more delicate lime flavor, pare the skin from 2 limes with a sharp knife, removing the white pith. Segment the flesh, chop into bite-sized pieces and add as a garnish.