Well, its totally depend upon the collages. Every collage has different criteria for selecting a teacher which comes up with different expectations. But in a general sense the most of the collages prefer people with Certification courses, Bachelor degree and Masters in field of commercial cookery.
There are many certifications available like Certificate III and Certificate IV in Commercial Cookery which will help you get your deserving job. If you are also looking for a collage and country where you would purse this course then you may purse it from Australia. Because commercial cookery industry is on a boom there.
One of the best collage which has good expertise in this domain is Stanley Collage in Australia which will give you a proper knowledge about the course.