Combine the beef, onion, paprika, garlic, and broth in the slow cooker.
Cook on low for 8 hours or high for 4-6 hours.
About 20 minutes before the beef is finished cooking, cook the egg noodles according to package directions. Drain and rinse in hot water.
When the beef is finished cooking, stir the sour cream into the beef mixture.
Serve the meat and sauce over the noodles and sprinkle with parsley.
Notes
*To thicken the paprikash sauce with cornstarch:*In a small bowl, combine 1 tablespoon of cornstarch with 1/2 cup of cold water. Stir thoroughly until no lumps remain.*Take the liquid sauce from the crockpot, slowly whisk it into the cornstarch slurry, and keep stirring until it thickens.*You can add the sour cream to the sauce here or in the pot.*Return the now thickened sauce to the pot, and give it all a mix!