Mix the wine, port, beef stock, garlic cloves, bay leaves and shallot in a pan.
Bring the mixture to a boil and keep boiling for an hour or until the mixture has reduced down to 2 cups.
You can do this step up to a couple days ahead if you like and keep it covered and refrigerated.
Cook a beef or lamb roast with garlic and thyme, then pour all the fat from the roasting pan into a pan over a moderate heat.
Bring the wine mixture and boil, scraping any brown bits up.
Add salt and black pepper to taste and pour into a large gravy boat.
Discard the bay leaves and serve this red wine jus.