Winter truffles are generally cooked longer and at higher temperatures than the Périgord truffle, which is preferably used ‘raw’, unless it is part of the traditional preparation for foie gras. But raw does not necessarily mean fresh, even if freshly harvested truffles (the term is "cavée") will have the best flavour.
The trick is to capture this aroma when it is at its best. This means preparing bases from truffles that were harvested during the best season in order to use them outside of the truffle season.
Basic recipes
Preservation methods