To make the homemade prawn stock:
- Peel and devein the prawns, reserving the head and the shells.
- Heat a splash of extra-virgin olive oil in a saucepan over high heat. Add the prawn heads and shells and cook, stirring frequently, until they turn red and are very fragrant, 3 to 5 minutes. Use a potato masher to firmly smash the heads and shells – this will help release their beautiful flavour.
- Add the remaining stock ingredients and stir to combine. Bring the stock to a simmer. Cover, reduce the heat to low, and simmer for 1 hour, stirring occasionally.
- Strain the stock into a clean saucepan – that is, pass it through a fine mesh sieve, leaving the solids behind. Press down on the shells and vegetables to make sure you’re getting all of the liquid. Stir in the saffron threads, cover and keep the warm over very low heat.
To make the orzo:
- Heat a splash of extra-virgin olive oil in a large saucepan over medium heat. Add the onion and season with a generous pinch of sea salt. Cook, stirring occasionally, until translucent and softened, around 5 minutes. You want the onion to cook gently without it taking on any colour.
- Add the garlic and cook for 1 minute, stirring constantly so it doesn’t burn, then add the orzo and stir well to coat in the oniony/garlicky oil. Cook, stirring constantly, until the orzo begins to darken slightly, 2 to 3 minutes.
- Add the tomato puree and cook until it starts to darken, 2 to 3 minutes.
- Add the white wine and cook, stirring frequently, until the pan is almost dry, around 1 minute.
- Add the homemade prawn stock 200 ml at a time, stirring almost constantly and ensuring the stock is absorbed before adding more. Cook until the orzo is tender and the stock is mostly absorbed but the pan isn’t dry, 12 to 15 minutes. You may not need all the stock.
- Stir in the prawns and cook until they’re cooked through, 2 to 3 minutes. If necessary, add an extra ladleful of stock to ensure that the orzo isn’t dry.
- Remove the saucepan from the heat. Add the parsley and stir well to combine. Taste and adjust seasoning. Divide the orzo between bowls and serve with lemon wedges on the side for squeezing over – enjoy!