Prepare the Beef and Bacon: Pat the beef chunks dry with a paper towel, then season with salt and pepper. In a spacious, sturdy pot or Dutch oven, sauté the diced bacon over medium heat until it turns golden and crispy. Using a slotted spoon, transfer the bacon to a plate, leaving the flavorful drippings behind in the pot.

Sear the Beef: In batches, add the beef pieces to the pot, searing each side until browned, about 3-4 minutes per side. Add additional olive oil if needed.

Cook the Vegetables: In the same pot, add the chopped onion and carrots, cooking for about 5 minutes until softened. Incorporate the minced garlic and sauté for another minute, allowing the aromatic flavors to bloom.

Build the Base: Return the beef and bacon to the pot. Dust the beef with flour, tossing gently to ensure each piece is thoroughly coated. Cook for 2-3 minutes, stirring frequently, to toast the flour and create a thickened base for the stew.

Add Liquids and Herbs: Stir in the tomato paste, beef broth, and bouquet garni. Allow the mixture to simmer gently, deglazing the pot by stirring up any caramelized bits stuck to the bottom. Cover and reduce heat to low, allowing the stew to simmer for about 1 1/2 hours, or until the beef is nearly tender.

Add Mushrooms and Finish Cooking: Add the quartered mushrooms to the pot, stirring to incorporate. Continue simmering, covered, for an additional 30-45 minutes, until the beef is fork-tender and the flavors have melded.

Serve and Enjoy: Remove the bouquet garni and adjust seasoning with salt and pepper to taste. Serve hot, over mashed potatoes or with crusty bread for a hearty, warming meal.