Lower the heat to medium, return the prosciutto to the pan, then stir throughout the tomatoes (breaking them up collectively along with your spoon), tomato purée and mushrooms. Spoon 4 tbsp of water into the empty tomato can, swirl it spherical, then pour it into the pan. Cowl and simmer for 15-20 minutes or until the sauce has thickened and diminished barely, then return the hen to the pan and put together dinner, uncovered, for about quarter-hour or until the hen is cooked by. Season and scatter over the parsley to serve.