Preheat the Air Fryer: Preheat your 5- or 6-quart air fryer to 350°F (175°C) for 3 minutes.
Prepare the Cauliflower Mixture: In a medium bowl, combine the onion, finely chopped cauliflower, crushed garlic, ground turmeric, ground ginger, and ¼ tsp of ground cinnamon.
Spray the mixture with cooking spray.
Air Fry the Cauliflower Mixture: Carefully pull out the air fryer pan and basket.
Line the basket with parchment paper and place the cauliflower mixture in the basket.
Slide the pan and basket back into the appliance.
Maintain the temperature at 350°F and set the timer for 5 minutes to cook until the cauliflower is tender.
Prepare the Filling: Transfer the cooked cauliflower mixture to a bowl.
Add the crumbled feta, chopped almonds, and herbs to the bowl, then stir to combine.
Allow the mixture to cool.
You can also speed up the cooling process by spreading the mixture on a tray and placing it in the freezer for 5 minutes.
Assemble the Triangles: Stack 2 sheets of fillo pastry together, spraying each layer with cooking spray.
Cut the stacked pastry lengthwise into three strips.
Place a heaped tablespoon of the cauliflower mixture in the corner of one pastry strip, leaving a ½-inch border.
Fold the opposite corner of the pastry diagonally across the filling to form a triangle.
Continue folding to the end of the pastry strip, maintaining the triangular shape.
Place the fillo triangle, seam-side down, on a tray.
Repeat with the remaining pastry sheets, cooking spray, and cauliflower mixture to make 18 fillo triangles.
Spray the triangles with oil and dust them with extra cinnamon.
Air Fry the Fillo Triangles: Place half of the fillo triangles in the basket.
Maintain the temperature at 350°F and set the timer for 10 minutes.
Allow them to cook.
After 10 minutes, turn the triangles over and set the timer for an additional 10 minutes, or until the triangles are golden.
Transfer the cooked fillo triangles to a wire rack.
Repeat the cooking process with the remaining fillo triangles.