Heat a large skillet over medium-high heat and add olive oil.

Sauté chopped onion and minced garlic for about 3-4 minutes until fragrant and translucent.

Season the chuck roast with salt and pepper, then sear it in the skillet for about 4-5 minutes on each side until browned.

Transfer the beef to your slow cooker or Instant Pot.

In the same skillet, add the carrots, celery, and bell pepper, and cook for 3 minutes until slightly softened.

Deglaze the skillet by pouring in the beef broth and scraping up any flavorful bits stuck to the bottom.

Pour the broth mixture over the beef in the slow cooker or Instant Pot.

Add drained tomatoes, cumin, smoked paprika, oregano, and cayenne pepper, mixing to ensure beef is submerged in the broth.

Cover your slow cooker and set it to low for 6-8 hours, or use the Instant Pot on high pressure for 35 minutes.

When the timer goes off, let the steam release naturally for about 10 minutes, then open carefully. The beef should be tender enough to shred.

Stir in frozen peas, letting them warm through for a couple of minutes.

Adjust seasonings with final touches of salt and pepper.