Dice the apple into small cubes.

Combine apple, sugar, and lemon juice in a pot and heat over medium flame.

Once the apple releases its juices, add butter and cinnamon powder, then simmer until thickened.

Let the apple mixture cool slightly in a bowl.

Trim the crusts off the bread and flatten each slice with a rolling pin.

Place the apple mixture on one side of the bread and brush the edges with egg wash.

Press the edges with a fork to seal and prevent leakage.

Make small slits on the top of the bread and brush the surface with egg wash.

Bake in an air fryer at 180°C (356°F) for 8–10 minutes.