Season the beef generously on all sides with salt and pepper.

Heat olive oil in a skillet over medium-high heat and sear the beef until deeply browned on all sides.

Transfer the beef to the slow cooker or Instant Pot.

In the same skillet, sauté onion, carrots, and celery until softened.

Add garlic and tomato paste, stirring until fragrant.

Pour in red wine and scrape up browned bits; simmer for a few minutes.

Add crushed tomatoes and beef broth, then pour the mixture over the beef.

Add bay leaves, rosemary, and thyme.

Slow Cooker:

Cover and cook on LOW for 8–10 hours or HIGH for 5–6 hours until fork-tender.

Instant Pot:

Seal and cook on HIGH pressure for 70 minutes, then allow natural release for 15 minutes.

Shred or slice the beef and return it to the sauce before serving.