Prep the Roast: Pat the chuck roast dry with paper towels and season generously with salt and pepper.
Preheat your oven to 350°F (175°C). Sear your roast in a cast iron skillet. Sear it on all sides over medium-high heat for a few minutes until browned.
Add the can of golden mushroom soup, both cans of water, and Worcestershire sauce to large roasting pot, beef bouillon. Stir to combine.
Add the seared pot roast to the pot, then the quartered yellow onion to the pot. Nestle the carrot pieces around the roast.
Cover the pot tightly and place it in the preheated oven for 20-30 minutes. Reduce heat to 325°F (165°C) and cook for 3-4 hours, or until the roast is very tender and easily shreds with a fork.
Remove pot from oven, allow meat to rest 20-30 minutes on a plate. In a small bowl, whisk together the cornstarch and water to create a slurry. Remove carrots from pot and place in a bowl and keep warm until ready to eat. Strain remaining liquid into a small pot. Add water if needed. If not enough flavor add some beef bouillon and salt. now simmer for a few minutes and test flavor again. if ready, add the cornstarch slurry and simmer until the gravy thickens to your desired consistency.
Serve & Enjoy: Once cooked, shred the roast with two forks directly in the pot. Serve the pot roast over mashed potatoes, with carrots and gravy spooned on top. Garnish with fresh herbs, if desired.