Prepare beef: Pat beef cubes dry and season with salt and pepper. In a skillet, heat olive oil over medium-high heat. Brown beef tips for 2-3 minutes per side. Transfer to a 6-quart slow cooker.
Cook aromatics: In the skillet, sauté onion for 3-4 minutes until soft. Add garlic and cook for 30 seconds. Scrape into the slow cooker.
Add liquids: Pour beef broth, Worcestershire sauce, thyme, and paprika into the slow cooker. Stir in cream of mushroom soup. Mix well.
Slow cook: Cover and cook on low for 6-8 hours or on high for 3-4 hours, until beef is tender.
Thicken gravy: Whisk cornstarch and water to make a slurry. Stir into slow cooker and cook on high for 15-20 minutes until thickened.
Cook noodles: Boil egg noodles in salted water for 8-10 minutes until al dente. Drain.
Serve: Spoon beef tips and gravy over noodles. Garnish with parsley, if desired.