Steps

• 1

  Remove and discard the husk from the tomatillo. In a small pot of boiling water, add the tomatillo and cook for 3 minutes. Remove the tomatillo and reserve the cooking water.

• 2

  In a food processor or blender, add the tomatillo, cilantro, green onion, garlic, oil, mustard, 1/4 cup of reserved tomatillo cooking water, horseradish, Traeger Prime Rib Rub, and a pinch of salt and pepper. Blend the ingredients until smooth. Reserve 1/2 cup of the tomatillo sauce, and place in a covered container in the refrigerator for later.

• 3

  Place the steaks in a baking dish or large zip-top bag. Generously coat the steaks with the remaining tomatillo sauce. Cover and marinate in the refrigerator for 1-4 hours.

• 4

  When ready to cook, set the Traeger temperature to 450˚F and preheat with the lid closed for 15 minutes. For optimal results, set to 450° if available.

  450 ˚F / 232 ˚C

  00:15

• 5

  Insert the probe horizontally into the center of the steak. Place steaks directly on the grill grates and cook for 10 minutes. Flip and cook until the internal temperature reaches 130˚F, or desired doneness, 5 minutes.

  450 ˚F / 232 ˚C

  130 ˚F / 54 ˚C

  00:15

• 6

  Remove the steaks from the grill and allow to rest for 5 minutes before thinly slicing. Assemble the sandwiches by placing the sliced steak on a ciabatta bun. Top with reserved tomatillo sauce and arugula, as desired. Enjoy!