Trim excess fat from the beef chuck roast and cut it into large chunks.
Heat the olive oil in a large skillet over medium-high heat. Add the beef chunks and sear them on all sides until browned. Remove from heat.
In the crockpot, combine the chopped onion and minced garlic. Place the seared beef on top of the onions and garlic.
Pour in the beef broth, followed by Worcestershire sauce, dried thyme, salt, and black pepper. Stir to combine.
Cover the crockpot and cook on low for 8 hours, until the beef is tender and easily shredded.
About 30 minutes before serving, cook the egg noodles according to package instructions in a separate pot. Drain and set aside.
Once the beef is done, shred it with two forks inside the crockpot. If using, add the frozen peas and stir.
Serve the beef mixture over a bed of egg noodles and garnish with fresh parsley, if desired.