Preheat oven to 425 F and lighting grease 2-3 baking sheets.
Place the ham slices between two pieces of plastic wrap and pound the heck out of them using the flat side of a mallet or a rolling pin. Try to get them as thin as humanly possible before you feel your hand may fall off. It’s considered a good thing if you can pretty much see through it. Season the filets with salt and pepper and set aside.
In a food processor, pulse the oats until they turn into a course flour consistency. Mix with the panko and cheese and set aside in a bowl.
In another bowl, mix together the eggs with the mustard and set aside. Put flour in a separate bowl.
One piece at a time, dredge the pork in the flour (tapping off any excess), then the eggs, and then the oats until covered. Place on the baking sheet and repeat with the remaining pork.
Bake for about 15 minutes until it reaches an internal temperature of 165 F.
Mushroom Sauce
Meanwhile, rehydrate the mushrooms for 10 minutes in boiled water.
Heat a large nonstick skillet over medium high heat and add in one teaspoon of oil. Saute the mushrooms until browned. Add the remaining tablespoon of oil and the flour and stir until combined and pasty.
Stir in the rehydrated mushrooms with 2-3 tablespoons of the hydration water, and the can of milk. Stir constantly over medium heat until thickened and no longer lumpy, about 2-3 minutes. Remove from the heat, stir in the balsamic and season with salt and pepper, to taste.
Assembly
Serve the cooked schnitzel on a platter and top with the chopped parsley. Top each piece with a spoonful of the sauce and a good dousing of fresh lemon juice.