Heat oil in Dutch oven on medium-high heat.
Add beef in batches and brown on all sides.
Remove beef; set aside in a bowl.
In same pot, sauté onion until soft and golden.
Add garlic, cook for 1 minute more.
Stir in tomato paste, herbs, and Worcestershire sauce.
Return beef to pot, sprinkle flour, stir well.
Pour in beef broth; bring mixture to boil.
Add carrots, potatoes, and celery to pot.
Cover, reduce heat, and simmer 2 hours.
Stir occasionally to prevent sticking or burning.
Stew is ready when beef is fork-tender.
Remove bay leaves before serving.
Garnish with parsley if desired. Serve hot.