Make the pastry: In a bowl, whisk flour and salt. Rub the cold butter into the flour with your fingertips until it looks like coarse crumbs with some pea-sized bits. Drizzle in cold water and mix just until the dough comes together. Press into a disk, wrap, and chill for 30 minutes.

Mix the filling: In a large bowl, combine ground pork, onion, apple, breadcrumbs, stock, Dijon, Worcestershire, thyme, smoked paprika, garlic powder, salt, and pepper. Mix gently with a fork or your hands until evenly combined. Do not overwork.

Preheat the air fryer: Set it to 360°F (182°C) for 5 minutes. Lightly spray the basket or tray to prevent sticking.

Roll the pastry: On a lightly floured surface, roll the dough to about 1/8 inch (3 mm) thick. Cut circles for bases and lids. Aim for 8–10 small pies: about 3.5–4 inches (9–10 cm) for bases and 3–3.5 inches (7.5–9 cm) for lids. Re-roll scraps as needed.

Shape the pies: Line small silicone muffin cups or use your hands to cup and form the base circles around a heaping tablespoon of filling. Top with a lid. Crimp edges with a fork to seal. Cut a small vent on top. Brush with beaten egg and sprinkle seeds if using.

Chill briefly: Place assembled pies in the fridge for 10–15 minutes. This helps the pastry keep its shape and crisp better.

Air fry the first batch: Arrange pies in a single layer with space between them. Cook at 360°F (182°C) for 14–18 minutes, until the pastry is deep golden and the internal temperature of the filling reaches 165°F (74°C).

Rotate if needed: If your air fryer has hot spots, turn the pies or rotate the tray halfway through for even browning.

Rest and serve: Let the pies rest for 5 minutes. This keeps juices inside. Serve hot with mustard, pickles, or a crisp salad.