Crustacean broth

(Brodo di crostacei)

Makes approximately 3 litres (105 fl oz/12 cups)

300 g (10½ oz) prawn (shrimp) shells

3 tablespoons olive oil

2½ tablespoons extra virgin olive oil

200 g (7 oz) onion, roughly chopped

150 g (5½ oz) carrot, roughly chopped

200 g (7 oz) celery stalks, roughly chopped

40 g (1½ oz) garlic cloves, peeled and roughly chopped

200 g (7 oz) tomato paste (concentrated purée)

2 kg (4 lb 8 oz) fresh snapper bones (including heads), washed thoroughly and roughly chopped

2 whole blue swimmer crabs, cleaned and cut into quarters

100 ml (3½ fl oz) dry white wine

1.2 kg (2 lb 10 oz) ripe fresh tomatoes, roughly chopped

3.5 litres (122 fl oz/14 cups) water

Preheat the oven to 180°C (350°F/Gas 4). Place the prawn shells in a small roasting tin and toss with the olive oil. Roast for 10–15 minutes or until golden, stirring occasionally.

In a large saucepan, heat the extra virgin olive oil over medium–high heat and add the roughly chopped vegetables and garlic. Add the roasted prawn shells and tomato paste and sauté for 1 minute. Add the snapper bones and blue swimmer crabs and sauté for about 5 minutes before adding the dry white wine. Cook until the wine has evaporated then add the tomatoes and water. Bring the stock to the boil then reduce to a slow simmer and cook for 40–60 minutes, skimming occasionally. Discard the larger fish bones and strain the liquid through a fine strainer. Make sure you press the prawn shells while straining as extra flavour is stored in them. Strain again through a fine sieve or muslin (cheese cloth) to make sure all bones are removed and refrigerate. Crustacean broth can be made in advance and frozen in an airtight container for up to 2 months.