Season the roast generously with salt and pepper.
Heat a skillet over medium-high heat and sear the roast on all sides until browned.
Transfer the roast to the crockpot.
Add chopped onion and minced garlic on top of the roast.
Layer the sliced carrots and diced potatoes around the meat.
Pour beef broth and Worcestershire sauce over the ingredients.
Sprinkle dried thyme evenly over the top.
Cover the crockpot and set it to low for 8 hours or high for 4 hours.
Once cooked, shred the meat with two forks directly in the pot.
Serve hot, garnished with fresh parsley.