4 boneless chicken breasts
1/2 cup flour, seasoned with salt and pepper
2 tablespoons extra virgin olive oil
2 small zucchini, halved and sliced
8 ounces mushrooms, sliced
1 clove garlic, minced, optional
1/3 cup dry sherry (can use white wine or chicken broth)
1 (14 to 15 ounce) can diced tomatoes, or use about 2 cups fresh diced
kosher salt and ground black pepper, to taste
1 cup shredded mozzarella or cheddar cheese, or a combination