This is a classic Florentine pork roast of Tuscany, Arista alla Fiorentina. Like much Tuscan food, it has few ingredients so they must be of top quality.
In this case, it's just a pork loin roasted with rosemary, garlic, and black pepper, and a couple of whole cloves just to get wacky, in a Tuscan sense.
This is a totally succulent and aromatic piece of meat that is wonderful fresh from the oven, but it is also good (and frequently) served cold in a picnic or other al fresco setting. I know that because I read it, but also because that's how I ate the leftovers with a little mostarda...there was no need to reheat them.