Pre-heat oven 275 degrees
To prepare the glaze, place the beer, garlic, shallot, peppers, and brown sugar in a sauce pan and bring to a boil. Remove from the heat and stir in the mustard. Set a side until ready to use.
To prepare the steak heat a very large oven proof sauté pan with oil until smoking hot. Season the steak with salt and cracked black pepper. Place the steak in the pan and sear well on both sides about 6 minutes. Place in the oven and glaze well. Glaze about every 15 minutes until the steak reaches and internal temperature of 130 degree about 1 hour. Remove from the oven glaze once more then allow to rest about 5 minutes. Slice and serve warm.