Heat the oil in a large pan

Add the fennel seeds, carrots, celery and garlic, and cook for 5 mins until starting to soften.

Tip in the leeks, tomatoes and stock, season and bring to the boil

Then cover and simmer for 15-20 mins until the vegetables are tender and the sauce has thickened and reduced slightly.

Add the fish, scatter over the prawns and cook for 2 mins more until lightly cooked.

Ladle into bowls and serve with a spoon.