Heat a 3-5 quart dutch oven over medium-high heat on the stove. Add bacon and sauté until cooked through. Set bacon aside on a paper towel lined plate.
Add beef and brown on all sides, about 2-3 minutes. Remove beef to a plate and set aside.
Add chopped onions, carrots, and about 2/3 of the minced garlic. Sauté for 3-4 minutes until softened, then return the beef and bacon to the pot. Season with salt and pepper, then toss with flour until evenly coated.
Add wine, beef stock, pearl onions, tomato paste, and herbs. (The liquid should just cover the beef and veggies - you may need to add or remove some liquid depending on the size of your pot.) Reduce heat to low and simmer for 4-6 hours until the meat pulls apart easily with a fork.
As the beef finishes cooking, heat butter in a pan over medium-high heat. Add garlic and mushrooms. Sauté for 2-3 minutes, then add 1-2 cups of the sauce from the pot.
In a small bowl, whisk cornstarch with about 1 tbsp of water to make a cornstarch slurry. Slowly whisk the slurry into the pan with the mushrooms. Add the whole mixture to the large pot and gently stir until mushroom mixture is well incorporated. Continue to simmer for 5-10 more minutes before removing from heat.
Serve over mashed parsnips and cauliflower or another plain side like mashed potatoes or egg noodles.