Place the beef, pepper, onions, and garlic at the bottom of the slow cooker.
Season generously with salt, pepper, chipotle powder, cumin, and coriander, then mix to evenly coat the ingredients.
Pour the salsa verde over the mixture, ensuring everything is well covered.
Squeeze the juice of one lemon over the top.
Cover and cook on low for 6-10 hours, or until the beef is so tender it easily shreds apart with two forks.
Serve the flavorful shredded beef over rice, or use it as a filling for tacos or burritos.
