2 boneless, skinless chicken breasts
salt and pepper
2 tbsp. olive oil
8 oz. button mushrooms, halved
½ cup sweet marsala
½ cup beef broth
2 oz. prosciutto, chopped
2 tbsp. chopped fresh sage
2 tbsp. unsalted butter
Slice chicken breasts in half lengthwise. Place pieces, one at a time, in a resealable bag, then pound with a meat mallet until ¼" thick. Season both sides with salt and pepper.
Sauté 2 pieces of chicken in oil in a sauté pan until browned, 3-5 minutes. Turn and cook 2 more minutes, then transfer to a plate and tent to keep warm. Sauté remaining chicken in the same manner.
Cook mushrooms in the same pan over high heat, 5 minutes, or until beginning to brown. Add additional oil as needed to prevent burning. Deglaze with marsala, scraping up any browned bits, then add broth and bring to a boil. Simmer until liquid is reduced by half, 5 minutes.
Off heat, stir in prosciutto, sage, and butter until butter melts. Season with salt and pepper.