Preheat your oven to 300F.
Season the meat liberally with salt and pepper.
Cook the bacon until lightly crisp in a large skillet or in the bottom of a Dutch oven. Remove the bacon and set aside.
Add the pearl onions and sauté for a few mins, then add the mushrooms and cook until browned and juices are starting to come out. Remove from the pan and set aside.
Add 1 tbsp oil to the skillet and brown the seasoned meat. Work in batches so as not to overcrowd the pan. Set the browned beef aside in a bowl to catch all the juice.
Add the chopped onions, carrots, and celery to the pan and another tablespoon of oil if needed and sauté until the onions are softened.
Deglaze the pan with red wine and reduce for 3-4 minutes, scraping up any bits from the bottom.
Add 1/2 cup beef stock or broth, garlic, bay leaf, thyme, and parsley. Then, stir in the meat.
Transfer the mixture to an oven-safe casserole or Dutch oven and bake covered for about 2 hours or until the meat is very tender.
Remove herbs, and add reserved bacon, pearl onions, and mushrooms and thicken the sauce with a slurry of 2-3 tablespoons of flour to the reserved 1/2 cup beef broth.
Bake another 20-30 minutes until pearl onions are soft and the stew is bubbling.
Serve and enjoy with a sprinkle of fresh parsley on top.