Begin by washing and chopping onions, carrots, and celery into small, even pieces and set aside.

Rub the beef chuck roast with salt, pepper, and seasonings, letting it sit for about 10 minutes.

Optional: Sear the seasoned beef in a skillet over medium-high heat for about 3-4 minutes on each side.

Layer chopped onions, carrots, and celery in the slow cooker around the beef and top with minced garlic and beef broth.

Cover the slow cooker and cook on low for 6-8 hours or high for 3-4 hours until the beef is tender.

Shred the beef into pieces in the slow cooker and mix with the gravy.

Prepare mashed potatoes by boiling peeled potato chunks in salted water until tender, then mash until creamy.

Serve creamy mashed potatoes topped with the shredded beef and gravy, garnished with parsley and garlic bread on the side.