Place a wire rack in a rimmed baking sheet. Set aside.
Make the brine for the chicken by pouring the water in a large bowl and mix in ¼ cup Diamond Crystal kosher salt until it dissolves. Alternatively, you can pour 2 cups of pickle juice in a bowl to use as the salt water brine.
Cut the breasts into bite-sized pieces until you have about 28 uniform pieces total. Use a meat pounder to smush each piece until they’re about ½-inch thick.
Add the chicken to the prepared brine and cover and store in the fridge for only 15 minutes. If you’re using pickle juice, marinate the chicken in the fridge, covered, for at least an hour and up to 8 hours.
Plop the plantain chips in a food processor and process until a coarse powder is formed. You should end up with 2 cups of plantain crumbs.
Transfer half of the crumbs to a shallow bowl. (If you put all the crumbs in the shallow bowl, they will clump up as you coat the chicken.)
In another shallow dish, add the eggs, cassava flour, onion powder, garlic powder, smoked paprika, and ½ teaspoon Diamond Crystal kosher salt. Whisk together until a sticky paste forms.
Take the chicken out of the brine and pat dry with paper towels.
In batches, dip the chicken in the egg mixture, shaking off any excess. Coat the chicken with the plantain chip crumbs, gently patting them. Set the nuggets on the prepared wire rack in the rimmed baking sheet.
Add more plantain chip crumbs to the dish when it runs low. Continue coating the chicken pieces until finished.
Now, air fry the chicken nuggets in batches. Lightly spray the bottom of the air fryer with avocado oil spray and place the chicken nuggets in a single layer. Spray the tops of the nuggets with avocado oil.
Air fry at 400°F for 8 to 10 minutes or until the outside is golden brown and the center is fully cooked. If the nuggets are frozen, air fry for 14 to 16 minutes. Repeat until finished.