I've seen some tomato sauce recipes that call for a long cooking time to fully develop flavors, while others simply call for quick cooking (often in a wide pan) to preserve the fresh tomato flavor. Having dabbled in jam making, I understand where those quick-cooking recipes are coming from. But having made some tomato sauces that were a bit underdeveloped in flavor, I also sort of see where the long cooking folks are coming from. So my question is which technique is appropriate for which situation? When do you want a long-cooked sauce, and when do you want a quick-cooked sauce? For bolognese sauce, it's pretty obvious that it should be long-cooked, but I can't think of other examples.