01 - Preheat the air fryer to 350°F for 3 minutes to ensure proper cooking temperature.
02 - Unroll the croissant dough and separate into 4 individual triangles on a clean work surface.
03 - If desired, spread a thin layer of Dijon mustard onto each dough triangle for added depth.
04 - Place 1 slice of roast beef, 1 slice of ham, and 1 slice of cheese on the wide end of each triangle.
05 - Roll each croissant starting from the wide end, tucking in sides to enclose the filling completely.
06 - Place croissants seam-side down in the air fryer basket, leaving space between each piece.
07 - Lightly brush tops with softened butter if using for enhanced golden color and richness.
08 - Air fry for 7-8 minutes until golden brown and crispy. Let rest 2-3 minutes before serving.