1. Put the saffron threads in a small bowl. Pour enough of the stock to cover the threads, then set aside.

2. Melt 2 tablespoons of the butter in a large, heavy based pan over medium heat. Add the shallots and cook for about 2 minutes until beginning to soften. Add the rice and cook, stirring frequently, for about 2 minutes, until the rice turns translucent and is well coated.

3. Add a ladleful (about 1 cup) of the simmering stock; it will steam and bubble rapidly. Cook, stirring constantly, until the liquid is absorbed.

4. Continue adding the stock, about half a ladleful at a time, allowing each addition to be absorbed before adding the next - never allow the rice to cook dry.

5. After about 15 minutes, stir in the saffron-infused stock; the rice will turn a vibrant yellow and the colour will become deeper as it cooks. Continue cooking, adding the stock in the same way, until the rice is tender, but still firm to the bite. The risotto should have a creamy, porridge-like consistency.

6. Stir in the remaining butter and half the Parmesan, then remove from heat. Cover and let stand for about 1 minute.

7. Spoon the risotto into serving bowls and serve immediately with the reamining Parmesan