What is "persillade"

n. A French sauce of chopped parsley, garlic, and sometimes herbs, oil, and vinegar.

Persillade is a sauce or seasoning mixture of parsley chopped together with seasonings including garlic, herbs, oil, and vinegar.

In its simplest form, just parsley and garlic, it is a common ingredient in many dishes, part of a sauté cook's mise en place. If added early in cooking, it becomes mellow; but when it is added at the end of cooking or as a garnish, it provides a garlicky jolt. It is extensively used in French and Greek cuisines, as well as in Cajun, Louisiana Creole, and Québécois cuisines.

A classic French and Quebec bistro dish is Pommes Persillade, cubed potatoes fried in a small amount of oil, with persillade added at the end of the cooking, and can sometimes be combined with Quebec poutine to produce a hybrid dish called poutine persillade. Persillade is also popular in Louisiana; New Orleans chef Austin Leslie's signature dish was fried chicken with persillade.