Return the beef to the pot with the vegetables and add 3 tablespoons of the butter. Sprinkle with the flour and cook, stirring, for about 3 minutes. Add the reserved wine and deglaze the pot, scraping up all the browned bits from the bottom. Add the bacon and stock and bring to a boil. Skim off the scum that rises to the top; once the scum is removed, add the bouquet garni. Simmer, covered, over medium-low heat until the beef is very tender, about 11⁄2 hours. Remove the bouquet garni.