Tarragon Butter

Beurre d'Estragon (tarragon butter) teaches the cleanest rule of herb butters: protect the herb before it meets the fat. Tarragon scalded for seconds, cooled at once, and pressed nearly dry gives the butter a vivid green colour and a rounded anise perfume without wet, grassy harshness. The quick scald is the dish, not ceremony.

The original formula assumed a saucier who could pound eight ounces of tarragon in a heavy mortar, work it into a pound of butter, and force the whole batch through a tammy. Here the quantity is reduced to one quarter while its one-to-two ratio remains exact. A small processor replaces the pounding arm, and a fine-mesh sieve replaces the tammy. Those tools were brigade scaffolding and can change; the scalding, immediate cooling, thorough pressing, and final sieving must stay. One cook, one stove, one evening.

The finished beurre d'estragon should be cool, satin-dense, and green all the way through, with no visible water and no threads of stem. Before you begin, set out the ice bath and two dry towels: pressing the blanched tarragon nearly dry is the one step that decides the butter.