1/4 cup shallots, finely chopped 1/2 cup dry red wine 1/4 cup Marsala wine 3/4 cup demi-glace 2 Tablespoons red currant jelly 1-1/2 Tablespoons unsalted butter Salt and freshly ground pepper to taste
Using the same roasting pan, heat pan over medium-high heat. Sauté shallots until golden, about 2 minutes. Add red wine and Marsala wine to deglaze pan, scraping up browned bits on bottom of roasting pan. Reduce by about 1/3. Add demi-glace and red currant jelly; simmer, whisking until jelly is incorporated into the sauce. Add butter, whisking until thoroughly incorporated.
Remove pan from heat, adjust seasonings to taste with salt and freshly ground black pepper.
It is preferable to use the same pan that the roast cooked in so that you can get all the flavor that accumulated on the pan bottom during roasting.