Portobello mushrooms are the mature form of small brown cremini mushrooms. These giant mushrooms are very meaty and earthy-flavored. Whole, sliced and quartered portobellos are available in the produce department. The stems from portobello mushrooms are woody and should be discarded.
Use a mushroom brush to clean portobellos. Small soft brushes for this purpose are available in cookware stores.
Rice pilaf is a good accompaniment to this Italian-style chicken dish.