Mirepoix: onion + carrot + celery
The foundational French aromatic base
French
Mirepoix — the French combination of diced onion, carrot, and celery cooked together as an aromatic foundation — is one of the most foundational vegetable-vegetable pairings in all of Western cooking.
About this pairing
Mirepoix — the French combination of diced onion, carrot, and celery cooked together as an aromatic foundation — is one of the most foundational vegetable-vegetable pairings in all of Western cooking. The ratio is canonical: 50% onion, 25% carrot, 25% celery by weight (sometimes adjusted slightly). The vegetables are cut to uniform dice (small for delicate preparations, large for braises), sweated in butter or oil until softened without browning (or browned for darker preparations), and used as the structural and flavor foundation for stocks, soups, braises, sauces, and countless other preparations. Beyond French cooking, the same three-vegetable combination appears as soffritto (Italian cousin, often with the same ratio plus parsley and sometimes garlic), refogado (Portuguese/Brazilian variant), and as the structural base for Italian-American red sauce, French stocks (fond brun, fond blanc), American mother sauces, and an enormous range of cuisines that adopted French technique. The pairing's universality reflects how completely the three vegetables complement each other: onion provides sweet allium aromatics and structural moisture; carrot provides sweetness, color, and characteristic herbaceous notes; celery provides celery-specific aromatic complexity (phthalides) and additional structure. Together they form a complete savory foundation that supports almost any subsequent ingredient.
Pairing details
Flavor chemistry
Onion provides sulfur-containing volatiles (allyl sulfides, propanethial) that transform during cooking into sweet caramelized compounds; carrot contributes terpenoids and natural sugars; celery contributes phthalides (the characteristic celery aroma compounds), plus additional natural glutamates that boost the umami signature of the combined base. The three together provide a complete savory-aromatic foundation that contributes flavor to whatever subsequent cooking process happens on top of it.
Featured varieties
4 varieties that feature prominently in this pairing. Tap any variety for its full editorial profile.
Editorial notes
The cut size matters more than the ratio for most preparations. Fine dice (brunoise) for delicate sauces; medium dice (paysanne) for soups and stews; large rough dice (matignon) for stocks where the mirepoix is strained out later. The cook time also varies — mirepoix can be 'sweated' (low heat, no browning) for delicate preparations or 'caramelized' (medium-high heat, deeply browned) for dark stocks and rich braises. The same vegetables produce dramatically different foundations depending on these technique choices.