Place ground chicken in a mixing bowl. Add mustard and all seasonings, then mix until well combined.
Create five equal sized patties. Set aside on a plate or sheet pan.
Spread cornflake crumbs on a plate. One by one, lay each patty in the crumbs to coat, on both sides. Place to the side on a plate or sheet pan.
Cook in batches, placing two patties in the air fryer (depending on the size of your air fryer you might fit more or less). Air fry at 400 degrees for five minutes, flip, then cook for five more minutes. Let cool for two minutes before placing on bun.
While the patties cook, prepare your buns. Place 1 tbsp of mayo, 1-2 pieces of lettuce, and one slice of tomato on each top bun. Add one slice of cheese to each bottom bun. When the chicken has cooled, place a patty on each bun and close. Enjoy!
Notes
To reheat, air fry for five minutes from the refrigerator or eight minutes from the freezer.