Chop the bell peppers and onions into thin strips, and mince the garlic finely.

In a large skillet, heat oil over medium-high heat. Season the beef with salt and pepper, then sear for 3-4 minutes on each side.

Remove the beef, sauté the chopped onions and bell peppers in the skillet for about 5 minutes, then add garlic and cook for another minute.

Transfer sautéed vegetables into a slow cooker, place the seared beef on top, pour in broth and Worcestershire sauce, and sprinkle with Italian seasoning.

Cover the slow cooker and cook on low for 8 hours or high for 4 hours.

Once done, shred the beef and return it to the broth with the vegetables. Serve on crusty rolls with extra broth.