Lamb Broth with Haricot Beans

First, if you're using dried haricot beans, cook them. Drain off the soaking water then place the haricot beans in a pot, cover them with fresh cold water, bring up to the boil and cook until soft - about 45-60 minutes. When they're cooked, they should be completely tender with no bite. Drain the beans, but save 200ml (7fl oz) of the cooking liquid.
Put a large saucepan on a medium heat and add the olive oil. Tip in the finely chopped onion and the finely chopped garlic, season with salt and freshly ground black pepper and cook for five minutes, covered, on a low heat until soft. Add the diced celery and the diced carrots and cook for 7-10 minutes until they are just soft. Add in the sliced leftover lamb, the haricot beans, the chicken stock or the lamb stock, whichever you're using, and the reserved bean cooking liquid, or the reserved liquid from the tin of beans, whichever you're using, and simmer for 15 minutes until all the flavours have mingled. Season to taste with more salt and freshly ground black pepper.
Serve in warm bowls with a drizzle of the parsley pesto - see the recipe below - over the top.

Parsley pesto

If you have a large pestle and mortar, first add the crushed garlic clove with a pinch of salt and pound it until smooth. Next, add the pine nuts and pound until they are coarsely crushed. Then, add the chopped parsley leaves and pound together with the pine nuts and garlic until you have a coarse paste. Lightly mix in the freshly grated Parmesan cheese using the pestle, followed by all of the extra-virgin olive oil. Taste and add more salt if necessary.
Alternatively, if you'd like to use a food processor, put the the crushed garlic, the pine nuts, the chopped parsley leaves and the freshly grated Parmesan cheese into the food processor and whizz up until coarse. Add the extra-virgin olive oil and a good pinch of salt and taste, adding more salt if necessary.
Pour the pesto into a sterilised jar and cover with 1cm (½in) of extra-virgin olive oil and store it in the fridge, where it will keep for up to three months.