Defrost puff pastry sheet.
Pre-heat oven to 400 degrees.
Pound veal cutlets with meat pounder until very thin.
Dredge in flour.
Put 1 tablespoon oil and 1 tablespoon butter into frying pan. Add more oil if you need to.
Fry cutlets until browned (but not too brown). Drain on paper towels. Set aside.
Set cutlets aside.
In clean pan, use remaining oil and butter to soften shallots and mushrooms (over medium low heat). Don't brown shallots, just soften.
Add in wine and brandy. Be careful and use a lid immediately to prevent a grease splash. Remove lid to continue cooking.
Simmer until alcohol has evaporated and there is a sauce, but no juice.
Roll out puff pastry to 14 x 14 square. You may need to flour your surface first.
Cut into 4 pieces.
Layer cheese prosciutto, veal, mushroom sauce, and garnish with some time or chopped parsely).
Add black pepper.
Fold and using water crimp edges closes.
Place on baking sheet seam side down.
Brush with egg wash.
Bake for 15 minutes at 400 degrees.