Remove the meat from the pan. Cover with foil to rest.
Add the oil or bacon fat to the hot pan, if needed, along with the shallot and wine.
Cook, scraping the bottom of the pan, until all the fond is released and the shallot is soft.
Continue to cook until the wine is well reduced. The mixture should be very syrupy and thick, and there should be no more than ¼ cup left in the pan.
Add the stock and simmer again until reduced by at least half.
Remove from the heat and taste for seasoning. Do not season before reducing, because your sauce will be too salty.
Add a little salt and/or pepper if needed.
Swirl in the butter, a bit at a time. Adding this fat is an optional step, but it helps to make the sauce silky and tends to round out the flavors.
Swirl in the herbs right before serving.