Cook the ground beef with the taco seasoning according to package directions. Set the taco meat aside to cool a bit.
Mix together the refried beans with 1/4 cup of the taco sauce and the 1/2 teaspoon of salt until well blended.
At this point you can store both the beef and beans in air tight containers in the refrigerator for up to three days... if you are only going to be making one or two Mexican pizzas at a time.
When ready to make a pizza, spread a full tablespoon of the refried bean mixture on each of two tostada shells.
Top one shell with 3-4 tablespoons of taco meat and a couple of tablespoons of shredded cheese.
Sandwich the two shells together. Spread a generous tablespoon of taco sauce on top of the Mexican pizza.
Top the pizza with another two tablespoons of shredded cheese and add a few chopped tomatoes.
Carefully place the Mexican pizza into the basket of your air fryer.
Cook the pizza at 400 degrees F for 5 minutes, or until the cheese is melted and starting to brown.