In this vegetarian rendition of chicken piccata, a medley of mixed mushrooms steps in as a substitute for chicken, maintaining the zesty caper-infused sauce. The combination of oyster, cremini and shiitake mushrooms adds the most flavor, though you can choose a single mushroom variety if you have a preference. Streamline your prep by opting for pre-sliced mushrooms, a timesaving hack for this flavorful dish.