Remove corned beef from packaging and thoroughly rinse from brining liquid. Pat dry with a paper towel.
Rud beef with mustard and seasoning.
Place meat on preheated smoker and cook at 225°F until internal temperature reaches 165°F. (See notes on times and temps).
Wrap smoked corned beef brisket in butcher paper. Pour in 1 ounce of apple cider vinegar and an ounce of Irish whiskey to help baste the beef with moisture. Place wrapped beef back on the smoker and continue to cook until the internal temperature reaches 200°F.
Allow the corned beef to rest for 20 minutes, then slice and serve.
Video
Notes
Prep: You can add the mustard and seasoning to the beef up to 24 hours before smoking it to let it absorb the flavors.Storage: Store leftovers in the refrigerator in an airtight container for 3-4 days.Timing: This is a 5–6 hour + cook (like brisket).
2–3 lb corned beef cooks in about 4–6 hours
4–5 lb corned beef cooks in about 6–8 hours
Faster Option: Cook at 275°F and wrap at 150°F to finish in about 4–5 hours instead of 6+. Wrapping earlier shortens the stall dramatically.