Preheat the oven to 400°F. Spray two large baking sheets with cooking spray.
Lightly brush or spray both sides of the tortillas with olive oil or cooking spray and place in a single layer on the prepared baking sheets. Lightly season with salt.
Bake for 5 minutes, flip them over, and bake for another 4-5 minutes until the tortillas are crispy like a tortilla chip.
Remove from the oven and serve with toppings such as refried beans, shredded cheese, chicken tinga, carnitas, or ground beef.
Notes
Air fryer instructions: Place 1-2 corn tortillas in the air fryer basket and put a small ramekin dish (or other heat-safe dish, like a coffee mug) on top to keep them in place. Air fry at 390℉ for 3-4 minutes, adjusting the tortilla halfway through so that the parts underneath the ramekins are also air-fried.
Keep a close eye. Tostadas can go from undercooked to burnt very quickly! So keep an eye on them while in the oven or air fryer.
Batch it. These tostada shells are super easy to batch. Just make your desired amount and then store them in a cool, dry place for 1-2 weeks.
Use different tortillas. Tostada shells are traditionally made with corn tortillas, but you can use flour tortillas if you prefer. Just note it will have a fluffier texture and won’t be as crispy.