Even on UA (gasp!), Kosher business class meals are served on regular business class china and include the same number of courses as the normal offering. UA gives the kosher caterer unused dishes from each class of service for the caterer to plate kosher meals. The cabin crew can then mix the dishes into the regular stock for dishwashing and reuse as part of the normal (non kosher) stock.
Obviously this takes a lot of coordination so if an airline has a low volume of kosher meal requests it may not be justified.
Charles