Remove the pork tenderloin from its packaging and place aside.

Mix the olive oil, soy sauce, garlic, brown sugar, dijon mustard, and salt and pepper into a bowl then add to a Ziploc gallon bag.

Add the pork tenderloin to the bag, close it, and cover it with the marinade. Marinate the pork for 30 minutes, but up to 5 days while refrigerated.

Preheat the air fryer to 400 degrees.

Remove the pork tenderloin from the bag and place in the air fryer. Cook for 22 to 25 minutes flipping halfway through until it hits 145 degrees internally.

Let the air fryer pork tenderloin rest for at least 5 minutes, slice into medallions, and enjoy!