For marinade: combine the garlic, bay leaves, carrots, celery, onions and wine in a large bowl or container. Add beef. Cover and let sit in frig for at least 4 hours or overnight. (Do not skip this step- it makes a huge difference in the flavor.)
For the stew: Remove beef from marinade. Strain veggies and bay leaves from the marinade and discard them. Reserve 2-2 1/2 cups of the marinade. Preheat oven to 350 degrees.
Coat a large wide pan or dutch oven with 2 T olive oil. and bring to med high heat on stove. Sprinkle the beef with the kosher salt and toss in the flour. Do not flour the beef until you are ready to brown it. Add the flour coated beef to the hot pan, be sure not to crowd the pan, you will need to work in batches to get it all browned evenly. Each batch takes 12-15 minutes to brown. Remove from pan onto baking sheet as you work. After the first 2 batches, deglaze the pan with 1/2 cup of the reserved marinade, scraping bits off pan. Drain the liquid into a small bowl. Add more olive oil to the pan and resume cooking the next batches of meat.
Add bacon to the pan and cook until browned, about 5 minutes. Toss in the mushrooms, carrots, celery, garlic and onions and season with salt and pepper. Cook until the mixture starts to soften, about 10 minutes.
Add tomato paste and cook 1-2 minutes. Add remaining one cup of marinade and deglaze the pan, scraping any browned bits, 1 minute. Add the beef back into the pan, stir to combine and cook until the wine has reduced by half, 1-2 minutes. Add enough of the beef stock to just cover the surface of the beef. Toss in bay leaves and thyme in a tied bundle. Cover the pan and bring liquid to a boil. Remove from heat and place in the oven.
Cook the beef for 2 hours, during the last hour, add the potatoes. Cover the pan with the lid and put stew back in the oven for an additional hour.
Remove the pot from the oven and skim off any excess grease from the stew. Remove thyme and bay leaf bundle. Serve with french crusty bread and garnish with chives.