Bring the vegetable stock (or chicken stock) and saffron just to the boil in a medium-sized saucepan over high heat. Remove from the heat and set aside.
Heat the olive oil and half of the butter in a large, deep frying pan (or stockpot) over medium heat. Add the onion and cook until softened (approximately 3 minutes).
Stir in the rice and after 2 minutes, pour in the wine. Cook, stirring, until all the liquid has been absorbed. Add a ladleful of the hot stock, stirring constantly. When the stock has been absorbed, stir in another ladleful. Continue to add ladleful’s of stock, stirring and allowing each ladleful to be absorbed before adding the next until the rice is ‘al dente’ (approximately 15 minutes).
Remove the frying pan (or stockpot) from the heat. Stir in the remaining butter and Parmigiano Reggiano. Serve with a grated Parmigiano Reggiano on top – buon appetitio.
Chicken stock adds a deep, rich flavour, while vegetable stock creates a lighter risotto. We prefer to use vegetable stock as traditionally Risotto alla milanese is served with rich meats like Osso bucco alla milanese, however if you want a tasty, meatier flavour, use chicken stock.