At the bakery, this flatbread is formed in long loaves, this version for home cooking adapted for a baking sheet. In place of the Old Bay seasoning, you can season the potatoes and mushrooms with salt and pepper instead.

Storage:
If not using within 24-48 hours, double wrap with plastic wrap and put in freezer for up to 1 month.  Defrost by thawing in the refrigerator at least 24 hours before rolling.

Double Blanche the fries to get them crispy.