Sear beef roast on all sides, rotating every 3-4 minutes, so that it forms a golden brown crust on all sides. Remove from pan and place in slow cooker if you didn't use the stove-top-safe slow cooker insert.
Add all remaining ingredients to the slow cooker: garlic, rosemary, celery, carrots, tomatoes, beef broth, wine and remaining 2 teaspoons of kosher salt.
Heat on Low for 8 Hours.
To serve, remove beef from slow cooker and let rest 10 minutes. Shred with fork is slice against the grain. Serve with vegetables on the side and fresh parsley.