Pat the beef dry and rub with herbs, salt, pepper, anaheim pepper, and garlic. Refrigerate for 1 hour up to 24 hours. Prep an instant pot with the rack inside and fill with enough water to cover the beef. Heat the water to 132 degrees for medium rare.
Place the beef in a ziploc bag with 4 tbsp of butter. Remove as much air as possible and seal. Place the bag in the instant pot. Close the lid and sous vide for 24 hours. Remove the bag from the pot. Remove the beef from the bag and pat dry, saving the liquid. Heat a skillet with 1 tbsp of oil over medium-medium high heat. Sear the beef on all sides until browned. Remove the beef, set aside, and wipe out the skillet. Continue making the gravy. Slice the beef and serve with the gravy.
If using an immersion circular, fill a heat safe container with enough hot water to cover the beef. Attach the circular and set it to 132 degrees. When the water reaches temperature add the meat and cook for 24 hours. To finish the beef follow the instructions above.