Ham & Cheese Croissant Recipe

Preheat and prep croissants

Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper or lightly grease it. Using a sharp knife, carefully slice each croissant horizontally about two-thirds of the way through so the top remains attached like a hinge.

Butter & mustard

Evenly spread about 1/4 teaspoon of the softened butter on the inside of the top half of each croissant. Spread about 1/2 teaspoon Dijon mustard on the inside of the bottom half of each croissant (adjust to taste).

Place one slice of Swiss cheese on the bottom half of each croissant so it slightly overhangs the edge (this helps melt and bind). Fold two slices of ham (or layer as desired) on top of the cheese. If using tomato or spinach, add 2–3 thin tomato slices or a small handful (about 1/4 cup) of spinach leaves on top of the ham. Add the remaining slice of cheese on top of the fillings for extra melt, if desired.

Close the croissant gently but firmly so the fillings are snug. Brush the exterior top of each croissant with the remaining softened butter (about 3/4 tablespoon total across 4 croissants). Sprinkle a little black pepper and the chopped chives over the top if using.

Arrange assembled croissants on the prepared baking sheet, leaving space between them. Bake in the preheated oven for 8–12 minutes, until the cheese is melted and the croissant is warmed through and the exterior is lightly crisped. If you prefer a browner top, place under the broiler for 30–60 seconds—watch closely to avoid burning.

Remove from oven and let rest for 1–2 minutes. Serve warm with extra Dijon on the side if desired.