In a large bowl, combine the red wine, beef stock , brandy, onion, carrots , garlic, parsley stems, thyme, rosemary, peppercorns, cloves, allspice , and bay leaf . Stir well to blend . Add the beef, and stir. Refrigerate, covered, overnight.
The next day drain the beef, reserving the marinade and vegetables separately. Pat the beef dry with towels, and season it well with salt and pepper. Preheat oven to 275 degrees.
Cut the slab bacon the long way into 1/4-inch-thick slices; then cut these slices into lardons that are 1/2-inch long. Cover the lardons with cold water, bring to a boil, turn down the heat, and simmer for 3 minutes. Remove the lardons and reserving.
Add 2 tablespoons of butter and 1 tablespoon of olive oil to a large Dutch oven set over medium heat. Dry off the lardons, add them to the Dutch oven, and cook stirring often, until they are golden. With a slotted spoon transfer the lardons to paper towels to drain .
In the same Dutch oven , over high heat, brown the drained and dried-off beef in the remaining bacon fat, in batches so the meat browns evenly. When you are done, pour off all but 1 tablespoon of fat. Return all of the browned beef to the pot.
Add the vegetable and herb mixture reserved from the marinade, and cook over medium-high heat, stirring, for 5 minutes.
Add the reserved marinade liquid and tomato paste . Bring the liquid to a boil, and taste it for seasoning. Cook in the oven, covered for 3 hours.
After 3 hours, Remove meat and strain sauce. Skim the fat from the stew .
Make the vegetable garnish : Place the pearl onions in a skillet, cover them with water, add 1 tablespoon of butter, the sugar, and salt and pepper to taste. Simmer the onions over medium-high heat until they are almost tender. and raise heat to high, and reduce the cooking liquid to 2 tablespoons. Continue to cook the onions, shaking the pan over the heat, until the onions are golden brown and glazed.
In another skillet set over medium-high heat, melt 3 tablespoons of butter; add the mushrooms. Add reserved lardons and salt and pepper to taste. Cook mixture, tossing often, for 7 minutes, or until golden brown.
Meanwhile, prepare the beurre manie: Cream together 1 tablespoon of softened butter with 1 tablespoon of flour. Roll the mixture into pieces the size of peas .
Add the cooked onions and mushrooms to the stew. Bring the liquid to a simmer, and add enough beurre manie, bit by bit, stirring constantly, to lightly thicken the sauce .
Divide the boeuf bourguignon among 6 dinner plates. Serve immediately.