Step 1

Gently unfold the puff pastry and set one aside. Lightly brush one sheet with egg wash and save the remaining egg wash for the top of the croissants. We’ll make nine square croissants, three from each column of unfolded puff pastry. Smear about a teaspoon of mustard onto each column of pastry, three per column. Sprinkle with a heaping tablespoon of grated cheese and layer with a folded piece of ham.  Gently drape the second sheet of puff pastry over the first. Use your fingers to firmly press the edges and then the edges around each slice of ham and filling. Try to press out as much air from each square as possible.

Step 2

Use a sharp knife to cut 9 squares.  Place on a parchment lined baking sheet, cover loosely with a kitchen towel and refrigerate while the oven preheats.

Step 3

Place a rack in the upper third of the oven and preheat oven to 400 degrees F. Remove the pastries from the refrigerator and arrange on the baking sheet about 2-inches apart. Brush with egg wash and sprinkle with sesame seeds if using.

Step 4

Bake for 20-24 minutes or until puffed and golden and bubbling around the edges.  Remove from the oven, allow to cool for at least 15 minutes before enjoying warm. Croissants are best the morning they’re baked but will last wrapped at room temperature for 2 days. Toast in the oven to refresh.