Add the pecan halves to a bowl and fully coat with the egg white, water, and vanilla. Let this sit for a minute or two.
While this is sitting, combine the sugar, cinnamon, and salt into a small measuring cup and mix together.
Start slowly coating the pecans with the sugar mixture. It's best to add a little bit then stir them up and continue adding the sugar. Do this until they are fully coating with the sugar mixture.
Spray the basket of the air fryer or Ninja Foodi with grapeseed oil spray or you can also use parchment paper for the air fryer.
Add an even layer of pecans to the air fryer and air fry at 320*F for 8-10 minutes.
Continue to cook in batches until you have worked through all the pecans, this took 3 batches for us in the Ninja Foodi Air Fryer.
Notes
If you do not want to use 1 cup of sugar, you can do 1/2 cup sugar, 1/2 Tbsp cinnamon, and 1/4 tsp of salt, then if you see that is not enough add more.