In a ziplock bag or between two sheets of plastic wrap, pound the chicken breasts with a meat mallet until they are about 1/4 inch thick.
In a shallow pan or dish mix the coconut flour, 2 tsp salt, and 1 tsp pepper.
Heat a large skillet over medium-high and then add the coconut oil.
Once the oil has melted, dredge the chicken breasts in the flour mixture and then add to the pan. Cook for about 5 minutes on each side until golden brown. (Do this in batches if they don't fit in the pan easily). Transfer to a plate when done.
Reduce the heat to medium and add a tablespoon of butter (or more coconut oil) to the pan and once melted, add the mushrooms. Cook, stirring frequently, until most of the moisture is gone from the mushrooms. Season with salt and pepper.
Add the marsala wine and bring to a boil. Scrape any brown bits from the bottom of the pan.
Add the chicken stock and bring to a boil. Add the remaining butter if using and stir the mixture once it has melted.
Return the chicken back to the pan and simmer for a few minutes to heat the chicken back up. Season the chicken if necessary with more salt and pepper and garnish with parsley.
If you don't buy pre-sliced mushrooms, use the slicing disc on your food processor to slice them in seconds.