Preheat the oven to 350º.
Sauté the bacon over medium heat for about 3 minutes, in a large dutch oven until crisp and browned. Transfer with a slotted spoon to a large dish and set aside. Leave the oil in the pan.
Pat dry beef with paper towel; cut into two inch cubes and sear in batches in the hot bacon fat until browned on all sides. Move beef to the same side dish as the bacon.
In the remaining bacon fat, sauté the carrots and diced onions until softened, (about 3 minutes), then add 2 cloves minced garlic and cook for 1 minute. Do not cook the carrots and onions all the way as this will happen during the oven cook time!
Add the wine, herbs and enough bone broth so that the meat is barely covered. Then add the tomato paste. Bring to a simmer on the stove.
Cover, transfer to the lower part of the oven and simmer for 2 to 3 hours, or until the meat is tender. During the last 20 minutes add in the small potatoes. Cover and continue to cook.
Remove from the oven to a stove top burner.
Using a ladle, take as much of the liquid out of the pot as you can. Ladle it into a blender.
Transfer the sauce to a blender with the ½ tsp Xanthan gum and pulse for 15 seconds. Taste! Add salt to the sauce (we love Redmond Real Salt) and mix again.
Pour the sauce over the meat and vegetables.
Simmer the beef bourguignon for 2 to 3 minutes to heat through.
While the stew is warming, saute the mushrooms in batches, if necessary in the butter, until browned, add to the warm stew.
Garnish with parsley and serve immediately.