Heat the olive oil in a large skillet over medium-high heat.
Add the beef cubes in batches and brown on all sides, about 3-4 minutes per batch. Transfer browned beef to the crock pot.
In the same skillet, add the chopped onion and cook for 3-4 minutes until softened.
Add the minced garlic and cook for an additional 30 seconds until fragrant.
Transfer the onion and garlic to the crock pot with the beef.
Pour the beef broth into the crock pot.
Add Worcestershire sauce, dried thyme, dried rosemary, salt, and black pepper to the crock pot. Stir gently to combine.
Cover and cook on low for 6 hours until the beef is tender.
About 30 minutes before serving, melt the butter in a small saucepan over medium heat.
Whisk in the flour and cook for 1-2 minutes to create a roux.
Slowly whisk in 1 cup of the cooking liquid from the crock pot until smooth.
Pour the roux mixture back into the crock pot and stir well to thicken the sauce.
Cook the egg noodles according to package instructions until al dente, then drain.
Serve the beef and gravy over the cooked egg noodles.