Preheat oven to 350 degrees F (175 degrees C). Spray a baking sheet with nonstick oil spray.
Roll the thawed pastry out onto a flat surface. Spread Dijon mustard to taste on the pastry sheets. Cover pastry with a layer of prosciutto, then cheese. Roll the sheets, beginning at the long side. Cut into 1 inch thick sections. Arrange the sections on the prepared baking sheet.