Preheat your mini air fryer to 375°F (190°C).
Lightly spray the mini tostada shells with cooking oil or use a small spray bottle.
Assemble the tostadas by layering the shredded chicken (or preferred protein) on top of each tostada shell.
Add the shredded cheese and diced tomatoes to each tostada.
Place the assembled tostadas into the air fryer basket in a single layer.
Air fry at 375°F (190°C) for 5-7 minutes, or until the cheese has melted and the tostadas are golden brown and crispy.
Once done, carefully remove the tostadas from the air fryer.
Top with shredded lettuce, sour cream, and salsa (optional).
Serve immediately and enjoy!