Someone asks us most weeks why we do not just use a blender. The honest answer is that a stone mortar bruises the herbs instead of liquefying them, and that difference is most of the flavor. A blade cuts cleanly through a lemongrass stalk; a pestle tears it, and the tearing is what releases the oils sitting just under the surface.
It is slower — about forty minutes a batch, done fresh every morning before the doors open. On a busy Saturday that means someone is at the mortar before six. Nobody has ever suggested changing that, not even during the years the kitchen was short-staffed.
You will know the paste is ready when it stops smelling like separate things and starts smelling like one thing. — from the family notebook
That is the only instruction the notebook gives for timing, and it is the one every new cook has to learn by nose rather than by clock. It usually takes a few months before it clicks. After that, nobody needs the recipe card again.
