Persillade
France — classical French cooking; particularly associated with Provençal and Lyonnaise traditions
Persillade is the French equivalent of gremolata — a simple mixture of finely chopped flat-leaf parsley and garlic that is used as both a finishing herb mixture and a crust element in French cooking. Where gremolata includes lemon zest and is always used raw at the moment of service, persillade can be used raw, cooked into a sauce, or combined with breadcrumbs to form a crust.
As a finishing herb mix, persillade is stirred into hot pan juices just before serving — the residual heat wilts the parsley slightly and tames the rawness of the garlic while preserving their fresh character. This technique is common in simple sautéed dishes: mushrooms à la persillade, provençale tomatoes, lamb chops, and pan-fried potatoes all benefit from a handful of persillade at the last moment.
As a crust (persillade de chapelure), the parsley and garlic are combined with breadcrumbs, olive oil, and sometimes a little mustard. This mixture is pressed onto the surface of a joint of meat or a fish fillet and roasted or grilled until the crumbs are golden and the persillade is fragrant. The Provençal version adds thyme and rosemary to the mix.
Persillade is also one of the components of sauce ravigote, gribiche, and various French herb vinaigrettes.
The proportion of garlic to parsley is always the cook's judgement — more garlic for strongly flavoured meats, less for delicate fish. The parsley should always be flat-leaf; curly parsley lacks the flavour for a proper persillade.