Ham & Cheese Croissant Recipe

Preheat and prepare croissants

Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper or a silicone mat. If the croissants are refrigerated, let them sit at room temperature 10–15 minutes to take the chill off for even heating.

Using a sharp serrated knife, carefully slice each croissant horizontally about two-thirds of the way through so the top lifts but remains attached (or slice completely if you prefer separate halves). Be gentle to preserve flakiness.

Prepare spread and butter

In a small bowl, stir the Dijon mustard with the softened butter until combined. This makes a lightly tangy butter that will melt into the croissant layers.

Spread about 1/4 tablespoon of the mustard-butter mixture on the cut interior of the bottom half of each croissant and a light smear on the inside of each top half.

Place 2 slices of ham folded or slightly fanned on the bottom half of each croissant so they cover the surface without overstuffing. Top the ham with 1 slice of cheese per croissant, tucking the edges slightly into the croissant so the cheese melts evenly.

Make egg wash

In a small bowl, beat the large egg with 1 tablespoon milk until uniform in color. Season with a small grind of black pepper if desired.

Close each croissant over the filling. Brush the exterior top and edges lightly with the egg wash to promote browning. If using, sprinkle chopped parsley on the brushed tops for color.

Arrange croissants seam-side down on the prepared baking sheet with a little space between them.

Bake

Bake in the preheated 350°F (175°C) oven for 10–14 minutes, until the croissants are heated through, the cheese is melted, and the tops are golden and glossy. If you like a crisper top, switch to the oven's broil for the last 30–60 seconds—watch closely to avoid burning.

Remove from oven and let rest 1–2 minutes before serving so the cheese sets slightly and avoids oozing.