Step 1: Place beef tips, onion, and garlic in a 6-quart slow cooker.
Step 2: In a small bowl, whisk together beef broth, soy sauce, Worcestershire sauce, tomato paste, thyme, and pepper.
Step 3: Pour the liquid mixture over the beef in the slow cooker.
Step 4: Cover and cook on LOW for 7-8 hours or on HIGH for 4-5 hours until beef is tender.
Step 5: About 30 minutes before serving, whisk cornstarch and water in a small bowl until smooth.
Step 6: Stir the cornstarch mixture into the slow cooker to thicken the gravy.
Step 7: Cover and continue cooking on HIGH for 20-30 minutes until gravy thickens.
Step 8: While the gravy thickens, cook egg noodles according to package directions.
Step 9: Serve beef tips and gravy over cooked egg noodles, garnished with parsley if desired.