Work area and utensils should be clean and sanitary.
Cut butterflied chicken breasts into half, yielding a total of four chicken breast medllions. Place on sheet pan and bake for 10 minutes at 350 degrees F. Chicken medallions should be fully cooked, set aside.
To a heated saute pan, add melted butter. Dredge chicken medallions in flour, shake off excess flour and add to saute pan. Add mushrooms, salt and pepper.
Saute chicken and mushrooms until thoroughy heated and golden brown. Add marsala wine and broth/demi-glace. Reduce by 50% and then add room temperature butter, let butter reduce into the wine/broth reduction until a thickened sauce forms.
To prepare Wilted Spinach: Add olive oil and garlic to a heated saute pan. Once oil is hot and garlic starts to turn golden brown, turn off heat and add spinach salt and pepper. Toss with olive oil until it becomes warm and starts to wilt.
Place wilted spinach on the side of a plate. Using tongs, remove the chicken medallions from saute pan and place next to spinach. Pour marsala sauce and mushrooms over chicken. Serve and enjoy!