Many dishes start with these core flavours in the UK, which tend to use equal parts of diced carrot, celery and onion.
The mirepoix is usually cooked in oil or butter to soften the vegetables before the other ingredients are added.
Occasionally, herbs such as bay or thyme will also be added.
Internationally, different styles of cuisine have varying versions of the mirepoix for example in Louisiana Creole or Cajun they call it the holy trinity – equal quantities of celery, onions and green bell peppers.
In Costa Rica it is olores – celery, onions, green bell peppers and garlic.
In Italy and Spain it is soffrito or sofrito respectively – diced carrot, celery, onion and garlic.
For Portuguese speaking nations it is refogado – onions, garlic and tomatoes.
All good mixtures of savoury, spicy and sweet to enhance the flavour of the overall dish.