Rick Stein serves up a taste of Venice with his John Dory alla carlina dish on Saturday Kitchen.

The ingredients for the fish stock are: 1 onion, chopped, 1 bulb fennel, sliced, 100g celery, sliced, 100g carrots, sliced, 25g button mushrooms, washed and sliced, 1 sprig thyme, 2¼ litres water, 1kg flatfish bones (such as brill, sole, plaice) or fillet.

For the tomato sauce: 6 tbsp olive oil, 4 garlic cloves, finely chopped, 1kg well-flavoured tomatoes, peeled or 2 x 400g tins chopped tomatoes, salt and freshly ground black pepper.

For the John Dory: 4 John Dory fillets, 50g plain flour, 2 tbsp olive oil, plus extra to serve, 1 lemon, halved, 1 tsp Worcestershire sauce, 2 small gherkins, finely chopped, 2 tbsp capers, 1 tbsp finely chopped and 1 tbsp whole, 2 tomatoes, peeled, de-seeded and finely chopped, 3 tbsp tomato sauce (see above), 250ml fish stock (see above) and small handful flatleaf parsley, chopped.