Mirepoix

What Is Mirepoix?

Mirepoix is a French aromatic vegetable mixture used as a flavour base for stocks, soups, stews, braises and sauces. The classic combination is onion, carrot and celery, traditionally in a ratio of two parts onion to one part carrot and one part celery by weight. The vegetables may be used raw, sweated in fat or browned, depending on the preparation and the flavour and colour required.

Classic Mirepoix Ratio

The standard 2:1:1 ratio provides a balanced base: onion contributes savoury sweetness, carrot adds sweetness and celery brings an aromatic, vegetal note. The ratio is a guideline rather than an absolute rule. Adjust it according to the dish, the stock or sauce being prepared and the strength of the other ingredients.

Choosing the Cut Size

The size of the mirepoix should match the cooking time and intended use. Smaller pieces release flavour more quickly and are suitable for short preparations such as fish fumet and court-bouillon. Medium pieces work well for stocks with moderate simmering times, while larger pieces are appropriate for longer-cooked stocks and braises. The goal is to extract flavour without allowing the vegetables to disintegrate too early.

• Small cut: useful for short cooking times and quick flavour extraction.
• Medium cut: suitable for many standard stocks and sauces.
• Large cut: useful for longer simmering preparations where the vegetables remain in the pot for an extended period.

White Mirepoix and Variations

For a pale stock or sauce, chefs may use a white mirepoix with ingredients such as onion, celery and leek, sometimes replacing carrot with parsnip to avoid adding colour. Other aromatic combinations may include leek, shallot, garlic, mushrooms, tomato or peppers, depending on the cuisine and recipe. These variations should be named or specified clearly rather than assumed to be the classic French mirepoix.

How Mirepoix Is Used

Mirepoix may be added raw to a stock, sweated gently in butter or oil, or browned to develop deeper flavour and colour. Because it is usually removed or strained from the finished liquid, the vegetables are generally cut for extraction rather than for final presentation. Trim cleanly and use sound vegetable trimmings where appropriate.

Chef’s tip: Choose the cut size and cooking method before preparing the vegetables. A small mirepoix in a long-simmered stock may break down too much, while large pieces in a short-cooked fumet may not release enough flavour.