Cawl (Welsh Lamb Broth with Leeks)

Variations

• With beef: ko.wikipedia records beef versions too. Use shin and give it another half hour.
• Bacon or a ham bone: a common way to bring salt and savour together. Cut the starting salt further if you do.
• Vegetables: parsnip, celery or onion get added, and rosemary instead of thyme. Do not drop the swede, though — the sweetness of the broth comes from it.
• Served as two courses: the broth first in a bowl, the meat and vegetables after with bread and cheese. Pot-au-feu uses the same architecture in France.
• The next day: eating it a day later is the traditional form, and it is why a fresh handful of leek goes in on reheating.
• The name: cawl is simply the Welsh word for soup or broth, so at home the dish is distinguished as cawl Cymreig — Welsh broth.

Tips

• A leek is not a kind of onion; it is an allium that never makes a bulb. What you eat of an onion is a storage organ — leaves thickened and packed underground. A leek does not build one. What you eat is the sheathed leaf bases stacked into a column. Two of this recipe's rules fall straight out of that.
• First, the grit lives between the sheaths. Washing the outside will never reach it, so split the leek lengthways and fan the layers under the tap. And cut long and cooked long, those same sheaths slide apart and scatter through the pot. Pot-au-feu records only the consequence — "Nothing survives three hours. They go in for the last 45 minutes in large pieces, and the leeks want tying with string or they come apart". The string is there because of the layering.
• Second, with no storage organ it cannot simply take the onion's place. Blooming spices puts the onion third in its order and describes it as "the slowest. Drive off water, develop sweetness." That instruction is about driving water out and building sweetness by browning. A leek is mostly water to begin with and its sweetness is already there; give it the same time and it does not gain flavour, it loses shape. So in this pot the leeks get the last five minutes, on a broth the lamb and swede have already spent two hours building.
• They are the only thing in the bowl that still tastes of itself. Everything else has spent two hours giving what it had to the liquid. That is why a dish whose name means nothing more than "broth" is known as a leek dish.
• Nothing is browned. Irish stew records the same habit in the next country — "Traditional Irish stew is a white stew: mutton, potato, onion and water, no searing, no flour and no stock." Cawl sits on that side too, and since a clear broth is the object, the fifteen minutes of skimming at the start earn their keep.
• Do not mash potatoes into it. That page leaves open the road of crushing a few floury potatoes for body; cawl does not take it. Waxy potatoes, cut large, left whole. Thickness is not what this bowl is after.
• Keep the swede. It is the one root that gives up sweetness without collapsing over a long simmer, and carrots alone do not fill the gap.
• The overnight is part of the method. Cooled, the fat sets into a sheet that lifts off cleanly, and meanwhile the meat and vegetables draw the broth back into themselves (reviving leftovers). The first day's leeks have given everything they had, though, which is why a fresh handful goes in as it reheats.