Heat the oil in a heavy large skillet over medium-low heat. Add the shallots, garlic, salt, and pepper, and saute until tender, about 1 minute. Add the peas and saute until heated through, about 5 minutes. Stir in the prosciutto and cook for 1 to 2 minutes. Add the parsley and remove from the heat. Season, to taste, with salt and pepper, and serve.