The meat mixture may be prepared in advance and stored in the fridge for quicker assembly of these pizzas when ready to eat. Double or triple the recipe as needed to serve a larger number.
For the sauce: combine the mayonnaise and ketchup in a small bowl, stirring to fully blend. Spread the mixture evenly over the pita rounds, leaving a small border. Distribute the beef mixture evenly over the sauce on each pita, and then evenly sprinkle the cheeses over the beef. If using, top with the tomato slices and pickles.
Carefully transfer to the baking sheet or stone and bake for 8 minutes, give or take a minute or two, or until the pizzas are hot throughout and the cheese is completely melted. Remove from the oven, and sprinkle with lettuce, if using. Cut the pizzas into 4 wedges each and enjoy.
Notes
*Standard white or whole wheat pitas with a 6-inch diameter may be used. When baked, white pitas will crisp slightly more than whole wheat. This recipe may also be made on a single crust or flatbread (gluten-free if necessary) with a 10-to 11-inch diameter. Feel free to make minor adjustments to cheese and toppings when varying the crust size.