All good things take time, and this carbonnade is no exception. The initial prep is simple enough, but it will need around two hours to fully develop in the oven. The result will be well worth the wait.
Cook the bacon in a large Dutch oven over medium heat until crisp. Remove bacon with a slotted spoon, reserving the drippings in the pan. Set bacon aside.
Cook beef, salt, and pepper in drippings over medium-high heat for 3 minutes, browning the beef well on all sides.
Add the garlic and cook for 30 seconds. Remove beef with a slotted spoon and set aside. Add onion to the pan, cover, and cook for 10 minutes, stirring occasionally.
Stir in the flour and cook for 2 minutes.
Add the broth, white wine vinegar, sugar, dried thyme, bay leaf, and the beer and bring to a boil. Return bacon and beef to pan.
Cover and bake at 325°F for 2 hours or until the beef is tender. Discard the bay leaf and serve over noodles.
Notes
Belgian ale is the most popular choice for carbonnade, but regular light or dark beer will also work. If you are worried about the flavor of beer in the end results, don't worry, it cooks out (same with its alcohol content). However, making the stew with beer infuses richness you wouldn't experience when using broth or stock. It's worth every last drop.
Don't be alarmed by the amount of onions called for here - after a couple of hours in the oven, the flavor of the onion is transferred to the meat and gravy, and the onions themselves will almost disintegrate.