Preheat oven to 425 degrees.
Thaw pastry sheets at room temperature for 40 minutes, until pliable.
Place foil on a 11 X 14 inch sheet pan. Grease foil with some olive oil.
Roll out pastry sheets to 11 x 14 inch rectangles.
Place one rolled out pastry sheet on bottom of pan.
Layer slices of ham on pastry sheet, overlapping slices and leaving about ½ to an inch on each side for sealing.
Top ham with a layer of evenly distributed gruyere cheese.
Top with a layer of cheddar cheese.
Sprinkle over a teaspoon of onion powder.
Sprinkle over red pepper flakes.
Using a pastry brush, brush the exposed edges of the puff pastry with egg wash.
Lay 2 puff pastry sheet over the top to cover, then press down and pinch the edges to form a seal around the filling.
Bake for 25 minutes or until puff pastry puffs up and is golden brown.
Cool 5 minutes, then serve. Enjoy!