Battuta is the soul of the Italian dish. Tomatoes? Cheese? They are important, but should be considered the legs on which the meal stands. Roughly translated, "battuta" means "base." Typically, battuta consists of lardo (LARD!), but bacon or pancetta can be substituted if the mere thought of lard makes your arteries congeal into a solid. Along with the fat, onion and garlic are added, making an aromatic Holy Trinity.
It is extremely important that the battuta be watched, and treated with loving care. Once the fat has been release from your, ugh, lard source (there's no sexy way to put that), add the onions until they are almost translucent. At this point, it is safe to add the garlic. Garlic should be added last, and you will understand why this is so important if you have ever experienced the unpleasant taste of burned garlic.
When the garlic has been fully incorporated, and you can really smell the aroma, you can add whatever other elements make up your dish. Crushed tomatoes can be added to make a lovely sauce, or this could be the base for a stew or braised dish.
The moral of this tale? Treat your battuta well, and you will be rewarded with a memorable meal!