by The Chocolate Dictionary

Similar to the Ensellure and Suprasternal Notch Tests, this is the test in which a lover is judged by whether or not one would enjoy eating or licking chocolates out of their navel. It involves judgements not just on how appealing his or her navel is, but also on the excitement that it generates. The Navel Dip Test is related to the ancient science of omphalomancy, or divination through the examination of the navel.  In 2002 Mars alluded to this test in their Maltesers campaign. A smiling woman, midriff exposed and a Malteser in her navel, was shown sprawled invitingly on a thick white rug, with the tagline “The lighter way to get him to do absolutely anything” making it clear what his course of action should be.

Maltesers advert from 2002.