Heat the oil in a large saucepan. Add the bacon and fry until it is crisp. Transfer the bacon to kitchen towels to drain.

Add 25 g (1 oz) (2 tablespoons) of butter to the pan and melt it over moderate heat. Add the onion and fry until it is soft. Add the peas and rice to the pan, reduce the heat to low and simmer, stirring frequently, for 5 minutes. Pour over the wine and approximately one-third of the stock. Regulate the heat so that the rice is bubbling all the time. Stir the rice occasionally with a fork. When the rice swells and the liquid is absorbed, add another one-third of the stock. Continue cooking the rice in this way until it is tender and moist but still firm.

Stir in the bacon, the remaining butter, salt and pepper and grated cheese and mix well to blend. Simmer for 1 minute, stirring frequently.

Serve at once.