Ingredients to serve 4

For the rouille

25g day-old white bread
a little fish stock or water
2 tbsp good-quality harissa
2 garlic cloves
1 egg yolk
250ml olive oil

For the soup

900g mixed fish such as gurnard, dogfish, cod and grey mullet
85ml olive oil
75g each onion, celery, leek and fennel, chopped
3 garlic cloves, sliced
juice of orange, plus 2 strips of the zest
200g tinned chopped tomatoes
1 small red pepper, deseeded and sliced
1 bay leaf; sprig of thyme; pinch of saffron
100g (4oz) unpeeled, cooked prawns
pinch of cayenne pepper
1.2 litres (2 pints) good quality fish stock
25g (1oz) Parmesan, finely grated, to serve

For the rouille, cover the bread with the fish stock or water and leave to soften. Squeeze out excess liquid and put the bread into a food processor with the harissa, garlic, egg yolk and ¼ teaspoon of salt. Blend until smooth.

With the machine running, gradually add the oil until you have a mayonnaise-like mixture. Fillet the fish, removing any bones. Heat the oil in a large pan, add the vegetables and garlic and cook gently until soft but not coloured.

Add the orange zest, tomatoes, red pepper, bay leaf, thyme, saffron, prawns, cayenne pepper and fish. Cook for 2–3 minutes, then add the stock and orange juice, bring to the boil and simmer for 40 minutes.

Meanwhile, make the croûtons (see below). Liquidise the soup and pass through a sieve into a clean pan, pressing out as much liquid as possible. Return the soup to the heat and season to taste with the cayenne, salt and pepper.

Ladle the soup into a warmed tureen and put the croûtons, cheese and rouille into separate dishes. To serve, ladle the soup into warmed bowls and leave each person to spread rouille on to the croûtons, float them on their soup and sprinkle them with some Parmesan.

To make croûtons, thinly slice a baguette then fry the slices until crisp and golden. Drain on kitchen paper and rub a garlic clove over one side of each piece.

My Kitchen Table: 100 Fish and Seafood Recipes by Rick Stein (£7.99,