Preheat the oven to 400°F.
Season beef cubes with salt and pepper and dust with flour.
Add 2 tablespoons olive oil to a Dutch oven, add beef cubes and sear until browned on each side (you may need to sear meat in batches to prevent crowding the pan). Transfer beef to a bowl.
Add beer to the pan and scrape up brown caramelized bits from the bottom.
Simmer to reduce beer by half. Pour beer over meat.
Add 2 tablespoons of olive oil to the pan.
Over high heat, add onions, celery and carrots. Season with salt and pepper.
After about 3 or 4 minutes, add garlic and allow vegetables to soften slightly.
Add beef mixture back to pan along with beef broth and return to a boil. Cover with a lid and transfer to preheated oven.
After about 10 minutes, check stew to make sure it is slowly simmering in your oven (don't boil the stew or it will toughen meat). Reduce oven temperature if needed to obtain a slow simmer.
After an additional 20 minutes, add potatoes, Brussels sprouts and thyme.
Return to the oven for another 40 minutes. If stew still has a lot of liquid, return the pan to the stove top and simmer with the lid off (this will help to reduce and thicken stew, as well as intensify flavor). Stir stew occasionally to prevent it from scorching on the bottom.
After a total of 1 1/4 to 1 1/2 hours cooking time, stew meat should be fork tender. Adjust seasoning with salt and pepper if necessary and serve immediately.