Preheat oven to 325°F (165°C).
Rub chuck roast with salt, pepper, and garlic powder.
Heat olive oil in Dutch oven over medium-high. Sear roast on all sides until browned.
Remove roast. Sauté onion, carrots, and celery in the same pot until softened.
Return roast to pot. Add broth, wine, bay leaves, and thyme.
Cover and bake for 3–4 hours, until beef is fall-apart tender.
Boil potatoes until fork-tender. Drain and mash with butter, milk, salt, and pepper.
Slice or shred roast. Serve over mashed potatoes with pan juices.
Notes
Use Yukon Gold or Russet potatoes for creamier mashed texture. Roast can be made ahead — flavor improves overnight. Optional red wine adds depth, but can be replaced with broth.
