Slice the bok choy, stems and leaves separately.

In a large frying pan, heat oil over medium high heat. Add the bok choy stems, mushrooms, and garlic. Cook 2 minutes; stir often.

Add the bok choy leaves to the pan. Cook 2 minutes.

In a small bowl, combine broth and arrowroot. Pour broth mixture and coconut aminos or tamari into pan.

Cook until sauce thickens and bok choy is tender. Stir often.