Trim any excess thick fat from the beef chuck roast and season all sides with sea salt, black pepper, garlic powder, and dried thyme.
Heat the olive oil in a heavy-bottomed pot or Dutch oven over medium-high heat.
Place the beef in the pot and sear for 3-4 minutes per side until a deep golden-brown crust forms, then remove the beef and set aside.
Add the diced onion, sliced carrots, and celery to the same pot, sautéing for 3 minutes to pick up the browned bits from the bottom.
Pour in the beef broth and return the beef to the pot, ensuring it is partially submerged.
Cover with a tight-fitting lid and reduce heat to low, simmering for 2.5 to 3 hours until the beef is tender enough to shred with a fork.
Remove the beef from the pot and shred it into large chunks.
Whisk the softened cream cheese into the remaining hot cooking liquid and vegetables until it is fully melted and the sauce is creamy.
Return the shredded beef to the pot, toss gently to coat in the velvety sauce, and serve hot.