Sauté aromatics: In a skillet over medium heat, cook the onion in a little butter or oil until soft, about 4–5 minutes. Add garlic and cook 30 seconds. Stir in spinach and let it wilt.
Set aside to cool slightly.
Make the filling: In a mixing bowl, combine chicken, bacon, cream cheese, sour cream, Parmesan, Dijon, thyme, smoked paprika, and the onion mixture. Season with salt and pepper. The mixture should be creamy but scoopable; adjust with a spoonful of sour cream if too thick.
Prep the air fryer: Preheat to 350°F (175°C) for 3–5 minutes.
Lightly spray the basket or a 7–8 inch round cake pan that fits inside your air fryer.
Layer the phyllo: Place one sheet of phyllo on a clean surface and brush lightly with melted butter. Lay it in the pan or directly into the basket, letting edges overhang. Repeat with 6–7 sheets, rotating each sheet slightly so the overhang forms a star pattern.
Keep unused phyllo covered with a damp towel to prevent drying.
Add the filling: Spoon the chicken mixture into the center and spread evenly, leaving about 1 inch from the edges.
Top and seal: Add 2–3 more buttered phyllo sheets on top. Fold the overhanging edges toward the center to enclose the filling. Brush the top with butter, and if you like, a light egg wash for shine.
Make 2–3 small slits on top to vent steam.
Air fry: Cook at 350°F (175°C) for 16–22 minutes, until the phyllo is deep golden and crisp. Start checking at 15 minutes. If the top browns too fast, tent loosely with a small piece of foil.
Rest and serve: Let the pie rest 5–10 minutes for cleaner slices.
Cut into wedges and serve warm.