In a skillet over medium heat, brown the ground beef, breaking it apart as it cooks. Once fully cooked, add the diced onion and seasonings, stirring until the onions become translucent. Remove from heat and let the mixture cool slightly.

Roll out the flaky pastry dough on a lightly floured surface to about 1/8-inch thickness. Cut the dough into circles roughly 4 inches in diameter.

Place a generous spoonful of the cooled beef filling in the center of each pastry circle. If desired, add a slice of cheese or a few pickle slices. Fold the pastry over the filling to form a half-moon shape and pinch the edges tightly to seal.

Preheat the air fryer to 375°F (190°C) for about 5 minutes. Arrange the assembled hand pies in a single layer in the basket and cook for 12-15 minutes, or until golden brown and crispy.

Let the hand pies cool for a couple of minutes before serving. Enjoy with dipping sauces like ketchup or mustard.