1. Shell the prawns and remove the heads. Leave the prawns to one side and place the heads and shells in a pan with 1 litre of water. Peel one of the garlic cloves and gently press with a knife until slightly crushed then add this to the water along with a small amount of salt (not too much as the cooked prawns will have already been boiled in salted water).
2. Bring to the boil and then simmer for 20 minutes. Drain, keeping the liquid as we’re just getting rid of the shells and then return the liquid stock to the pan and keep on a very low simmer.
3. Heat the olive oil and butter in a large, heavy-bottomed frying pan and cook the onion and the remaining garlic clove (crushed or finely chopped) along with a sprinkling of salt. Fry for a few minutes until tender. Keep the heat nice and low to avoid burning the garlic.
4. Add the Arborio rice and stir until all the grains are coated, then add a couple of ladles full of your homemade seafood stock. Bring to the boil and keep stirring until at least half it has been absorbed by the rice. Add the tomato puree and repeat the process with the stock until the rice is nearly cooked.
5. Just after adding some more stock near the end of the cooking, put the prawns and peas in the pan and heat through. Add more stock if required. The risotto will be ready when you have a thick consistency and the grains of rice still have a small amount of bite. Season and serve and don’t forget to gloat about the fact that you ‘slaved’ over the stove to make your own homemade prawn stock.
Little Buying Tip
You may not have bought ready-cooked whole prawns before so if you haven’t then keep an eye out at Asda that do the perfect prawns in 200g packs and they regularly have them on special offer.