Heat the stock in a small saucepan and keep warm. Heat the oil in a large sauté pan, over medium heat, until hot. Add the onion and sauté for 2 minutes. Add the pancetta and continue to sauté for 2 more minutes. Stir in the garlic and cook 1 more minute. Stir in the rice and sauté, until the rice is opaque, about 2 minutes. Start adding the heated broth ½ cup at a time, stirring constantly after each addition. Continue this process until all the broth has been added and the rice is al dente, about 18 minutes. Stir the peas, pepper, parsley and ½ of the grated cheese into the simmering rice during the last 3 minutes of cooking. Serve immediately in soup bowls and sprinkle each serving liberally with the remaining grated cheese.
In this version of the recipe frozen peas are substituted for fresh since fresh peas are seasonal, expensive and very time consuming to shuck. If you prefer to use fresh peas add them with the rice in the recipe and continue as directed.