Preheat your oven to 350°F (175°C). Heat olive oil in a large Dutch oven or heavy-based pot over medium heat. Add the chopped bacon and sauté for about 3 minutes until it’s crispy and browned. Use a slotted spoon to transfer the bacon to a plate, leaving the rendered fat in the pot.

Pat the beef chunks dry with paper towels and season with salt and pepper. Sear the beef in batches in the hot oil and bacon fat until browned on all sides, about 2-3 minutes per side. Remove the beef and place it on the plate with the bacon.

In the same pot, add the sliced carrots and diced onions. Sauté for about 3 minutes until they begin to soften. Add 4 cloves of minced garlic and cook for another 1 minute until fragrant. Drain any excess fat, leaving about 1 tablespoon in the pot.

Return the bacon and seared beef to the pot with the vegetables. Season with a pinch of salt and pepper. Sprinkle flour over the mixture, tossing well to coat the meat and vegetables. Let cook for 4-5 minutes to brown slightly.

Add the pearl onions (if using), red wine, and enough beef stock so that the meat is barely covered. Stir in tomato paste, crushed beef bouillon cube, thyme, and bay leaves. Bring to a gentle simmer on the stove.

Cover the pot with a lid and transfer it to the lower part of the oven. Let it cook for 2 to 3 hours or until the meat is fall-apart tender. Check occasionally to ensure the liquid is simmering very slowly—adjust the heat if needed.

In the last 5 minutes of the cooking time, prepare the mushrooms. Melt butter in a medium-sized skillet over medium heat. When the butter begins to foam, add the remaining 2 cloves of minced garlic and sauté for about 30 seconds until fragrant. Add the quartered mushrooms and cook for 5-6 minutes until browned. Set aside.

Remove the Dutch oven from the oven and carefully pour its contents into a colander set over a large pot to separate the sauce from the meat and vegetables. Discard the bay leaves and any other herb sprigs.

Return the beef, bacon, and vegetables back into the Dutch oven. Skim off any excess fat from the sauce and pour it back over the meat mixture. Add the prepared mushrooms on top of the meat.

Simmer the sauce for a minute or two to heat through, skimming off any additional fat that rises to the surface. Adjust the consistency by adding a few tablespoons of stock if the sauce is too thick, or simmer longer if too thin.

Taste for seasoning and adjust salt and pepper if needed. Garnish with fresh parsley and serve the Beef Bourguignon hot over mashed potatoes, rice, or buttered egg noodles.