In a small bowl, combine the chili powder, oregano, paprika, cumin, salt, and pepper. Sprinkle the roast evenly with the seasoning and rub it into the meat. Cut the roast in half or chunks to fit in the pot.
Press the SAUTE button on the Instant Pot and add 1 tablespoon of olive oil. When hot, add the roast to the inner pot and sear, about 2 minutes on all sides. Remove to a cutting board and set aside.
Add the remaining oil, then stir in the onion, jalapeño, and garlic. Saute for 2-3 minutes, then press CANCEL.
Add the broth and deglaze the pot.Return the beef to the pot, scattering some of the onions and jalapeños on top. Secure and seal the lid, then cook on MANUAL HIGH for 50 minutes.
When the cooking time is up, allow a 10-minute Natural Release, then open the pressure valve to quickly release any remaining pressure.
Carefully remove the lid and transfer the beef to a cutting board. Shred the beef with two forks, then return it to the Instant Pot. Stir in the lime juice. Taste and adjust seasonings, if desired. Serve in tortillas with your favorite taco toppings, orin burrito bowls or salads.