Combine the chicken stock and saffron in a saucepan over moderate heat and bring to a simmer.
1250 ml chicken stock, 1/2 tsp saffron
Heat the olive oil in a separate pot over moderate heat.
3 tbsp olive oil
Add the onion and cook until tender but not brown, about 5 minutes.
1 medium onion
Add the rice and cook, stirring constantly, for 3 minutes.
375 ml arborio rice
Add the wine and simmer over low heat until most of the wine is absorbed.
125 ml dry white wine
Add the chicken broth about 3/4 cup (180 ml) at a time, allowing most of the liquid to be absorbed before adding more, and stirring frequently as it cooks.
When most of the liquid has been absorbed and the rice is cooked "al dente," about 20 minutes, remove from the heat and stir in the butter and Parmesan cheese.
2 tbsp unsalted butter, 2 tbsp Parmesan, ground pepper, salt