In a small bowl whisk together chili powder, ground cumin, kosher salt, garlic powder, onion powder, smoked paprika, black pepper, ground coriander, and chipotle chili pepper to make the spice rub; set aside.
Pat the beef pieces dry with paper towels, then rub them liberally with the spice mixture, pressing the rub onto the meat; reserve any leftover spices for the pot.
Heat the vegetable oil in a large skillet or Dutch oven over medium-high until very hot, then sear the cubed beef on all sides until browned.
Transfer the seared beef to a 6‑quart (or larger) slow cooker. Add the reserved spices, beef broth, salsa, undrained diced green chiles, tomato paste, lime juice, brown sugar, liquid smoke, beef bouillon, and dried oregano; stir to combine.
Cover and cook in the slow cooker on HIGH for 3½–4½ hours or on LOW for 6–8 hours, or until the beef pulls apart easily with two forks.
Remove the beef to a rimmed plate or large bowl (do not discard the cooking juices). Shred the meat with two forks and discard any excess fat.
Return the shredded beef to the slow cooker and toss with the cooking juices. Cook on LOW for 20 minutes to allow the meat to absorb the juices, then taste and adjust with hot sauce, cayenne, additional lime juice, or brown sugar if desired.
Remove the beef with tongs or strain it in a colander so fillings like tacos and burritos don’t get soggy. Save the cooking liquid if desired for cooking rice or serving alongside.
