Place the chicken stock in a saucepan and heat gently.
Heat the olive oil in a heavy-based saucepan. Add the rice, brown for a few seconds and stir with a spatula to ensure the grains are coated with the oil.
Add a small ladleful of chicken stock to the pan, allow the rice to absorb the liquid, then add another ladleful of stock. Continue adding the remaining hot stock little by little, each time waiting until the last spoonful has been fully absorbed.
Remove the pan of rice from the heat. Add the diced butter and the grated Parmesan. Let it rest briefly before mixing in. The rice will take on a creamy consistency. Serve hot.