Preheat the oven to 300˚F.
Cook the bacon in a Dutch oven set over medium-high heat until crisp; transfer to a bowl.
Brown the beef in the pot, sprinkling with salt and pepper, then add the onion and garlic and cook for 2-3 minutes. Sprinkle with flour and stir to coat.
Add the stock, wine, tomato paste and thyme, cover and braise for 3-4 hours, until the meat is very tender.
Add the carrots and return to the oven for 15 minutes, until tender. In another skillet, heat the butter and sauté the mushrooms for 5 minutes, or until golden; stir them into the stew along with the bacon just before serving.