This was a very good recipe. I didn't have marsala on hand, and didn't want to run out and buy a whole bottle for the half-cup required, so I used a dry white wine (a blend). Other than that, I made as directed. I did throw the onions in a bit early as the shiitakes were finishing up just to save a few minutes. One reviewer mentioned thickening the sauce, but we liked the thinner sauce with the mashed potatoes.
This recipe was really good. The chicken cutlets I used were a bit thicker than 1/2 inch, so ai coked them about 4 min on each side and put them back into the sauce at the end to simmer in the sauce for a couple of minutes. I also ended up using more crimini mushrooms than shiitake and added a bit of garlic powder and a TB of corn starch to the liquid before pouring it in to flavor and thicken the sauce a bit more. I served it with sauteed broccoli and green beans and mashed potatoes. I would definitely make it again.
I followed the recipe exactly and was looking forward to a tasty dish...but it was very bland. Maybe could be improved with the prosciutto included in similar recipes? Also, two min. per side for 1/2 inch chicken cutlets wasn't long enough to cook the chicken, I cut each breast in half as recipe suggested (butterflied them) and had to cook them 5-6 min. per side.