In a mixing bowl, combine the 14 oz beef broth, cream of mushroom soup, dry onion soup mix, and minced garlic.
Stir until the mixture is evenly combined.
Reserve the additional 3 c of beef broth for later in the recipe.
Place the beef roast into the slow cooker.
Pour the broth and soup mixture over the roast.
Cover the slow cooker with the lid.
Cook on high for approximately 4 hours or on low for approximately 8 hours, until the beef is tender and can be pulled apart easily.
Using two forks, shred the roast directly in the slow cooker.
Add the reserved 3 c of beef broth to the shredded beef.
Stir until the beef and broth are evenly combined.
Cover the slow cooker again.
Cook on low for 3 hours or on high for 1 hour.
Prepare the egg noodles according to the package instructions.
Drain the noodles well.
Add the cooked egg noodles to the slow cooker.
Gently stir until the noodles are coated with the beef and sauce mixture.
Cover the slow cooker.
Cook on low for 1 additional hour, allowing the noodles to absorb the flavor of the beef mixture.
Taste and season with salt and black pepper as needed.
Serve warm.