Roast Lamb and Mint

Mint sauce is the cheapest sauce in the British kitchen to make and the easiest to get wrong. A handful of leaves comes off the stalks, gets chopped fine, and drops into a bowl with a spoon of sugar and a splash of vinegar, and that is the whole recipe. There is no cooking, no reduction, no emulsion to break. What pours out is a loose green slick that smells of vinegar a clear beat before it smells of mint, barely sweetened, mostly sour, the leaf left in as flecks rather than strained away. It is the one thing that takes cold lamb between two slices of bread and makes it the specific sandwich a British fridge produces on the Monday after a Sunday roast.

The reason it works is chemistry the lamb cannot do for itself. Cold off the joint, the meat is rich, the fat sets firm and faintly waxy, and a low muskiness trails each bite toward the back of the tongue. Sugar on its own would only flatter that. Acid on its own would strip it bare. Mint sauce runs both at once: the vinegar cuts the fat and scrubs the sheep note off the palate, the pinch of sugar keeps the sourness from turning raw, and the chopped leaf lays a cool green top-note that reads more as the smell of mint than its taste. This is the line that divides the sauce from its set, sweeter relative on the shelf. Mint jelly agrees with lamb. Mint sauce contradicts it, and the contradiction is what keeps each mouthful tasting of lamb rather than of the one before.

Take a bite of a good one and the order is precise. Meat, butter, and chilled crumb land first, dense and quiet for about half a second, and then the vinegar arrives late and sharp and pulls the fat clean off the tongue, leaving a herbal coolness and a few green specks on the lip.

The bread tells the truth about how the thing was built: where the sauce sat too thick, the lower slice has gone translucent and damp and a little sour-grey, so the sandwich is made with the sauce painted in a thin band and the lamb laid as a wall in front of it, butter sealing the crumb behind. Carve the meat thin and against the grain or the firmed fat refuses to soften and the chew hangs on past the swallow. The aftertaste is the proof: clean, faintly bitter with mint, the sheep pushed all the way to the back.

The sauce belongs to the Sunday table before it ever sees a sandwich. It sits in a sauceboat beside the roast leg at lunch, spooned over the hot meat, and it is still in the door of the fridge on Monday when the cold joint gets carved for packed lunches. Whether sauce or jelly is the correct article is a low, permanent argument in British kitchens, and most cupboards settle it by keeping both. The everyday version is a jar of Colman's or Garner's concentrate let down with water; the better one is a bowl made from scratch when there is mint going to seed in the garden. Order lamb at a British carvery and mint sauce arrives unasked, the way the gravy does, sometimes thinned into the crumb of a hot roll instead of a cold cut, which eats looser and juicier and is its own tradition.

Mint, the lamb, and the vinegar bowl

The pairing of mint with lamb is far older than Britain's claim on it, and the patriotic version should be held at arm's length. One often-repeated story has Elizabeth I confining the eating of lamb and mutton to bitter herbs, mint among them, to curb demand and protect the wool trade. It is a tidy tale with no firm documentary footing and is best filed as legend. The geography is more convincing than the throne: the food historian Dorothy Hartley pointed out that ewes dropped their lambs in the warm valley pastures where streams ran and mint grew thick, so the herb and the meat simply came up together, season by season, on the same ground.

What is solidly British is the form, not the idea: mint chopped raw into vinegar and sugar, a sweet-sour dressing rather than a cooked sauce. That recipe is on the page by the middle of the eighteenth century. Hannah Glasse set down a green mint sauce of bruised leaves steeped in vinegar and sugar in her 1747 cookbook, The Art of Cookery (the volume's title carries on, Made Plain and Easy), and she trusted the pairing so completely that she used it as a disguise, claiming a hindquarter of pork dressed lamb-fashion would, with mint sauce, eat like lamb. By 1816 it had hardened into a national tic worth a foreign professional's note. Louis Eustache Ude, a French chef who had cooked for Napoleon's household and then for the English aristocracy, wrote in his London cookbook that in France lamb went up with maitre d'hotel butter, but in England you sent it up with gravy under it and, in a sauceboat, mint sauce made with sugar and vinegar.

For all that the British treat it as theirs, the oldest record of the dish is Roman. Apicius, the cookery collection that carries a first-century gourmand's name, already gives a mint sauce to serve with roast lamb or suckling kid, and Pliny the Elder, writing in the same era, recommended mint at the table because it stirs up the mind, he said, to a greedy taste in meat. So the sandwich a British carvery hands over without asking, the pairing the country guards almost alone, was being spooned over roast lamb roughly seventeen centuries before anyone in England thought to call it peculiar.