Let the pork tenderloin rest at room temperature for one hour if you have time. If your pork tenderloin has silver skin (a silvery membrane), use a knife to remove it before beginning recipe. (Full disclosure: I never do this, but you're supposed to when making tenderloin.)
Lay five pieces of raw bacon parallel to each other on a clean surface. Take the remaining four pieces of bacon and weave them into the five pieces of bacon to make a bacon mat. (Check out the recipe video below for visuals!)
Season the pork tenderloin generously on all sides with the BBQ seasoning.
Carefully roll your bacon mat around the seasoned tenderloin. The pork tenderloin should be covered all along its length with the bacon mat. If you have a particularly long tenderloin, you could always add more slices of bacon to the ends.
Tie the bacon to the pork tenderloin with kitchen twine. Secure it in five places.
Put the pork tenderloin on an air fryer tray in the middle of the air fryer oven. (This is the lower rack position in my oven.) Air fry for 20 minutes at 400°F (200°C), flipping the pork tenderloin over after 10 minutes.
Remove the pork tenderloin from the air fryer and flip it again. Generously brush the top and sides with the BBQ sauce using a pastry brush. Return the pork tenderloin to the middle of the air fryer. Air fry an additional 10 minutes at 400°F (200°C).
Check the thickest part of the pork tenderloin with a meat thermometer to ensure it reached a minimum safe internal temperature of 145°F (63°C).
Let the pork tenderloin rest for 5-10 minutes before clipping the twine and cutting it into slices.