1 Put the stock powder in a large saucepan with 4 cups of water and bring to the boil over high heat. Reduce the heat to low and keep the stock at a simmer.
2 Heat 3 teaspoons of olive oil in a large heavy-based saucepan over medium heat. Add the leek and cook, stirring, for 5 minutes, or until soft. Add half the garlic and half of the zest and cook, stirring, for 1 minute, or until the mixture is fragrant. Add the quinoa and stir for 1–2 minutes, or until coated in the oil.
3 Add wine and simmer until reduced by half. Gradually add the simmering stock, a cup at a time, stirring constantly, and making sure that the stock is absorbed before you add more. The process will take about 15 minutes; the quinoa should be al dente yet creamy.
4 Stir in the peas and snow peas. Simmer for 2–3 minutes, or until the vegetables are just tender. Remove from the heat and stir in the parmesan and spinach. Cover risotto and set aside for 2 minutes. Season to taste with freshly ground black pepper.
5 Meanwhile, heat remaining oil in a large non-stick frying pan over high heat. Add prawns, remaining garlic and zest, and cook for 2 minutes each side, or until golden and just cooked through. Serve risotto topped with the prawns.