It isn't rocket science...but it sounds impressive.
Classically-trained chefs finely chop a trio of celery,
onions and carrots to create a mirepoix, a flavour base for stocks, stews,
soups and sauces that’s fundamental in numerous French dishes.
Leftover celery leaves won’t be discarded either, but thrown into stocks, poaching liquors and soups for a vegetal aroma.