Preheat the air fryer. Set it to 350°F (175°C) for 3–5 minutes. A preheated basket helps the croissants crisp evenly.

Prep the croissants. Use a serrated knife to slice each croissant horizontally. Don’t cut all the way through the back hinge if you want them to hold together better.

Spread a thin layer of mustard. This adds tang and helps balance the richness. Keep it light so the croissant doesn’t get soggy.

Add the ham. Fold 2–3 slices per croissant so they’re evenly distributed and not bunched in one spot. Layering helps the heat reach everything.

Add the cheese. Use 1–2 slices per croissant, depending on size and melt factor. Swiss or provolone melt gently; cheddar gives a sharper bite.

Close and secure. Gently press the tops to help the fillings settle. If needed, use a toothpick to keep the croissant closed while cooking.

Optional finish. Brush the tops with a little softened butter or a quick egg wash for a glossy, bakery-style finish.

Air fry. Place croissants in the basket in a single layer, leaving space between them. Cook at 350°F (175°C) for 5–7 minutes, flipping at the 3–4 minute mark if your air fryer browns unevenly.

Check for doneness. The tops should be crisp and deep golden, and the cheese fully melted. Add 1–2 minutes if needed, but watch closely to prevent scorching.

Finish and serve. Remove toothpicks, season with a crack of black pepper, and drizzle with a touch of honey if you like sweet-savory contrast. Serve hot.