Welsh Rarebit

A thick savoury paste of cheddar, ale, and English mustard, grilled onto toast until it blisters

Origin: Wales & England

From the journey of Mustard.

Welsh rarebit is not cheese on toast, and the difference is a cooked sauce and a great deal of mustard. The cheese is melted with ale and butter and flour into a thick, glossy, spreadable paste, sharpened with English mustard and Worcestershire sauce, spread over toast, and grilled until it blisters and browns. What comes out is savoury in a way that plain melted cheese is not, and the reason is largely the mustard: a substantial quantity of it, enough to be tasted clearly, cutting through what would otherwise be a mouthful of fat. The name has an unkind origin. It appears in the eighteenth century as Welsh rabbit, part of a family of English jokes in which a poor man's substitute is named after the thing he cannot afford, on the same pattern as a Bombay duck or a Scotch woodcock. Rarebit is a later genteel correction of a word that was never anything but a slur, and the argument about which is correct has been running for two centuries with no sign of resolution. The dish is a good illustration of how English mustard is actually used, which is not as a spread but as a seasoning inside cooking. Here it goes in early, dissolved into the sauce, and it survives because the sauce is never boiled hard; a rarebit made without it tastes flat and greasy, and no amount of extra cheese fixes it. A buck rarebit is the same thing with a poached egg on top, which is the standard pub version and improves it considerably.

Ingredients

Sauce

  • 25 g unsalted butter
  • 25 g plain flour
  • 150 ml brown ale or stout
  • 250 g mature cheddar, coarsely grated
  • 2 tsp English mustard, made
  • 1 tbsp Worcestershire sauce
  • 1 whole egg yolk
  • 0.5 tsp freshly ground black pepper

To Serve

  • 4 slices good white or sourdough bread, thickly cut

To Finish

  • 1 pinch cayenne pepper

Method

  1. Melt the butter in a small heavy pan, stir in the flour, and cook the roux over a medium heat for two minutes without letting it colour.
  2. Add the ale a splash at a time, beating smooth after each addition, until you have a thick smooth sauce. Simmer for two minutes.
  3. Turn the heat to its lowest and add the grated cheddar in three handfuls, stirring until each is fully melted before the next goes in.
  4. Take the pan off the heat and stir in the mustard, the Worcestershire sauce, and the black pepper.
  5. Beat in the egg yolk. Leave the mixture to cool for ten minutes until it is thick enough to spread and hold its shape.
  6. Toast the bread on both sides. Spread the mixture thickly right to the edges, leaving no bare crust.
  7. Grill under a hot grill for three to four minutes until bubbling, blistered, and browned in patches. Dust with cayenne and serve at once.

Notes

The mixture keeps for four or five days in a sealed jar in the refrigerator and is arguably better after a day, so it is worth making a double quantity. It also freezes. A mature farmhouse cheddar is right. Anything mild is pointless and anything young releases too much water. Caerphilly is the Welsh choice and is excellent, though softer. For a buck rarebit, top each finished slice with a poached egg. A Scotch woodcock, from the same family of jokes, is scrambled egg on anchovy toast and has nothing to do with either bird. Milk can replace the ale and gives a milder, more childproof version. What cannot be reduced is the mustard, which is the whole reason the dish is not simply cheese on toast.

The Gastrographer

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Ingredient originTrade or transit route
Became a culinary stapleColonial / trade control
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