Knives. Herbs. Careful step-by-step preparation. Chef or assassin; it's really only feasible to be one at a time.
On the other hand, the chef to assassin vocational retraining program recently created by the assassin guild is a resounding success, or at least if you frequent the right kind of people.
Among chefs lots of people are hard working and detail-oriented, but hate the flashy part of the job: more and more elaborate new recipes, focus on foreign gear and on the right way to cut an onion.
And they won't complain about the late work hours.
Meanwhile, being an assassin is a much more down to earth occupation: nobody will mock you because of the knife you use, well because they risk being stabbed, but also because the only valid criteria for the trade is if the contract is fulfilled and if you didn't to a mess.