01 - Preheat your oven to 325°F.
02 - Pat the beef roast dry and season generously with salt and pepper on all sides.
03 - Heat vegetable oil in a large Dutch oven over medium-high heat. Sear the roast on all sides until deeply browned, approximately 4-5 minutes per side. Remove and set aside.
04 - In the same pot, add onions and garlic. Sauté for 2-3 minutes until fragrant.
05 - Add carrots, celery, and baby potatoes to the pot. Stir to coat with the aromatics.
06 - Return the roast to the pot, nestling it among the vegetables. Pour in beef broth, water, and Worcestershire sauce. Sprinkle in thyme, rosemary, and add bay leaves. Bring to a simmer.
07 - Cover the pot with a tight-fitting lid and transfer to the oven. Braise for 2.5 to 3 hours, until the beef is fork-tender.
08 - Boil russet potatoes in salted water until fork-tender, about 15-20 minutes. Drain well and mash with butter and milk. Season with salt and pepper to taste.
09 - Steam or boil green beans until just tender, approximately 5 minutes. Drain thoroughly, toss with butter and garlic powder.
10 - Remove the roast and vegetables to a serving platter. Discard bay leaves.
11 - Skim excess fat from the pot juices. In a small bowl, whisk cornstarch with cold water until smooth. Bring the pot juices to a simmer on the stovetop, whisk in the cornstarch mixture, and cook until thickened, 2-3 minutes. Adjust seasoning as needed.
12 - Slice or shred the pot roast. Serve with braised vegetables, creamy mashed potatoes, green beans, and rich gravy.