In a large oven-safe pot or Dutch oven, heat the olive oil over medium-high heat.
Brown the arm roast on all sides.
Remove the roast from the pot and set it aside.
In the same pot, sauté the onions, carrots, celery, and garlic until softened.
Stir in tomato paste and cook for 1-2 minutes.
Deglaze the pot with red wine, scraping up any browned bits from the bottom.
Return the arm roast to the pot and add beef broth, thyme, and rosemary.
Bring the liquid to a simmer, then cover the pot and transfer it to the preheated oven.
Braise for 2.5 to 3 hours or until the meat is fork-tender.
Check the seasoning and adjust with salt and pepper if needed.
Notes
For a richer flavor, you can add mushrooms or root vegetables during the last hour of braising. Serve the braised arm roast with mashed potatoes or crusty bread for a complete and satisfying meal.