Preheat air fryer to 350 degrees Fahrenheit.
Line the air fryer basket with a large piece of foil.
Remove the brisket from the packaging and set the pickling seasoning packet aside. Rinse the corned beef under cold water. Then, pat it dry with paper towels. Place the brisket into the foil lined basket
In a medium sized bowl combine the apple cider vinegar, Dijon mustard, brown sugar and garlic powder. Pour the mixture over top of the brisket, making sure to fully cover it.
Next, open the seasoning packet and sprinkle that over the top of the brisket evenly.
Place brisket into the air fryer and set the timer for 40 minutes.
When timer goes off check brisket, and baste it by using a spoon to collect the juices at the bottom of the foil spooning them on top of the meat. You can use a teaspoon or two of water as well if needed.
Set timer for an additional 15-20 minutes.
Check temperature of the meat using a meat thermometer. The internal temp should be at 145 degrees.
Allow to rest for ten to fifteen minutes. Then slice brisket against the grain for tender results!