Prep your air fryer: Preheat to 350°F (175°C) for 3–5 minutes. A hot basket helps the pastry puff and crisp.
Get the puff pastry ready: Unfold the sheet on a lightly floured surface.
If it’s too soft, chill it for 5 minutes. Cut into 4 rectangles for classic pain au chocolat style, or triangles if you prefer a crescent roll shape.
Add the chocolate: Place a line of chocolate (about 1–1.5 tablespoons) on the short edge of each rectangle. If using batons, lay one along the edge and another near the center for extra chocolatey layers.
Roll it up: Roll the pastry over the chocolate, tucking it in as you go.
Seal the final edge by pressing gently so it doesn’t unroll. For triangles, roll from the wide end to the tip and bend into a crescent.
Brush with egg wash: Beat 1 egg with a teaspoon of water and brush over the tops. Sprinkle with coarse sugar or sea salt flakes if you like.
Air fry in batches: Lightly spray the basket or line with parchment.
Place croissants seam-side down with space between them. Cook at 350°F (175°C) for 7–10 minutes, until deep golden and puffed. Thicker pastries may need 1–2 minutes more.
Cool briefly: Let them rest for 5 minutes.
The chocolate is lava-hot right out of the air fryer and will set slightly as they cool.
Finish and serve: Dust with powdered sugar or drizzle with melted chocolate. Serve warm for the best texture and flavor.