Combine parsley flakes, olive oil, salt, pepper, and mustard in a small bowl. Rub evenly over turkey. Place turkey in a 6-quart Instant Pot, and add chicken broth. 

Cover Instant Pot, and, using manual setting, set to 18 minutes on high pressure, making sure the pressure valve is sealed. When done, let the pressure slowly release.

Let stand at least 5 minutes before slicing.