Barely Warming Pre-Cooked Crab

Dungeness crab is sold already cooked, so the only job at the stove is to take the fridge chill off it; the moment you actually cook it again, the meat tightens, dries and loses its sweet, silky flake. Melt a little butter over low heat, add the picked crab, and warm it for just 30 to 60 seconds, folding gently so the lumps stay intact. It should feel barely warm to the touch, not hot. On this dish the warm soup is poured over at the table and brings its own heat, so the crab needs nothing more. Season at the end with a little salt and lemon zest, after warming, so the brightness stays fresh. The same restraint applies to any pre-cooked shellfish: lobster, prawns or lump crab are all best gently brought to temperature rather than re-cooked.