Ingredients

•          500g/1lb 2oz prawns in shells, peeled and black vein removed, shells and heads reserved (or 350g/12oz peeled prawns)
•          1.3 litres/2¼ pints water (or light fish stock)
•          1 small brown onion, finely chopped
•          1 stick celery, finely chopped
•          1 small fennel bulb, finely chopped (optional)
•          pinch salt
•          5 tbsp extra virgin olive oil, plus extra to serve
•          320g/11½oz risotto rice
•          100ml/3½fl oz dry white wine
•          1 lemon, zest only
•          1 tbsp roughly chopped fresh parsley (optional), to serve

Method

1.     To make the prawn stock, put the reserved heads, shells and tails in a pan and cover with 1.5 litres/2¾ pints of cold water. Add a pinch of salt, bring to a gentle boil, then simmer for 20 minutes. Strain the prawn stock into a clean pan and keep warm at the back of the stove. If you are using peeled prawns, put the fish stock in a pan and warm.
2.     Put the olive oil, chopped vegetables and a pinch of salt in a large, deep saucepan or flameproof casserole. Cook the vegetables over a medium-low heat until soft and starting to turn translucent. Add the rice and stir so every grain is coated with the oil.
3.     Add the wine and let it evaporate. Make a note of the time, and start adding the prawn stock or fish stock a ladle at a time, stirring the rice attentively and vigorously until all the liquid is absorbed, before adding the next ladleful. Continue adding the stock ladle by ladle, adding the prawns after 16 minutes, working on the principle the cooking time will be 17–20 minutes depending on the rice. Keep tasting. It is ready when the rice is plump and firm but without any chalky bite. The risotto should be soft, fluid and creamy.
4.     Remove the pan from the heat and stir in a tablespoon of olive oil and some lemon zest, to taste. Add a pinch of chopped parsley if using, and serve.