Open your canned apple pie filling. If the apple slices are very large, give them a rough chop into smaller, dice-sized pieces. This helps the tortillas roll up easily and prevents tearing. Set aside.

Briefly warm the flour tortillas (10-15 seconds in the microwave) just to make them pliable. Lay a warmed tortilla flat. Spoon about 1-2 tablespoons of the apple filling mixture across the center, leaving about half an inch border on the sides. Do not overfill, or it will leak in the air fryer.

Roll the tortilla tightly from one edge to the other, creating a sealed log. If you are struggling to keep the edge sealed, a tiny dab of water on the final seam can help. Place the rolled taquitos seam-side down on a plate.

In a small bowl, melt the butter until smooth. In a separate, wide shallow dish, mix the sugar and cinnamon together well. If using, add a pinch of nutmeg or allspice.

Brush the entire surface of each taquito generously with melted butter. Immediately roll the buttered taquito in the cinnamon-sugar mix until completely coated.

Preheat your air fryer to 380°F (195°C). Place the taquitos in the air fryer basket in a single layer, ensuring they don't touch. Depending on your air fryer size, you may need to work in batches.

Air fry for 6-8 minutes, flipping them carefully halfway through (around the 4-minute mark). They should be a beautiful, deep golden brown.

Remove the taquitos and let cool for just 1 minute. Serve sprinkled with extra cinnamon sugar and your favorite toppings like ice cream, caramel sauce, or whipped cream.