In a medium pan over medium heat, cook ground beef, green peppers, red peppers, and onions until ground beef is browned and onions are transparent.
Stir in taco seasoning and water. Remove from heat and allow to cool.
Roll pie crust out on a non-stick surface. Using a round bowl or cup (one with a 5-inch diameter works perfectly), cut out three circles from one of the pie crusts.
Combine the remaining dough and roll out with a rolling pin to a similar thickness to the original crust. Cut a fourth circle. Repeat this process with the other pie crust = 8 pieces total
Once beef mixture is cooled, spoon 2-3 tablespoons on each circle and top it with a sprinkle of cheese. Fold each circle of dough in half and use a little bit of water to seal the edges. Use a fork to press around the edges.
Whisk the egg and brush each empanada with it. Place empanadas (4 at a time) in a greased air fryer basket. Preheat air fryer for 5 minutes to 350 degrees.
Cook at 350 degrees F for 5-7 minutes or until tops are as golden brown as you'd like. Serve with your choice of sour cream, salsa, guacamole, lettuce, tomatoes etc.