A whole orange egg yolk with pepper and salt rests in dark brown sauce in a small stemmed glass beside a cruet of malt vinegar on a polished wooden bar against a dark green wall. — A Prairie Oyster: a whole egg yolk in Worcestershire sauce and malt vinegar in a small wine glass.

Prairie Oyster, Egg Yolk in Worcester Sauce from 1920s London

Name: Prairie Oyster
Prep time: 3 min
Total time: 3 min
Cuisine: British
Ingredients: 2 tsp Worcestershire sauce; 1 pasteurized egg; 1 pinch cayenne pepper; 1 pinch salt; 2 tsp malt vinegar

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A whole egg yolk in Worcester sauce and malt vinegar, with red pepper and salt on top: the Prairie Oyster of Harry MacElhone’s London bar book of the 1920s, with no alcohol in it.

By Forgotten DrinkPublished October 25, 2026

Recipe makes: 1 glass
Prep: 3 min
Total: 3 min

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A Prairie Oyster: a whole egg yolk in Worcestershire sauce and malt vinegar in a small wine glass.

The story behind the recipe

The Prairie Oyster is a raw egg yolk in a small glass of Worcester sauce and vinegar, seasoned and swallowed whole, and it has no alcohol in it. Harry MacElhone, then of Ciro’s in London and later of Harry’s New York Bar in Paris, printed it as No. 199 in his ABC of Mixing Cocktails. The book is undated; a note on the same page about a cocktail he made for Princess Mary’s wedding in February 1922 puts it in 1922 or after.

Sauce, yolk, pepper, vinegar

MacElhone’s method takes one sentence. Two spoonfuls of Worcester sauce go into the glass, then “drop the yolk of a Fresh Egg without breaking,” a little red pepper and salt go on top, and two spoonfuls of malt vinegar are poured over. The “oyster” is the yolk, sitting whole like an oyster in its shell.

It holds no tomato, but its sharp, salty sauce is the seasoning that later went into the Bloody Mary. The Bloody Mary’s Other Names sets it beside the vodka drinks of 1939 and 1942; with tomato juice instead of an egg, the Dodge Hotel Tomato Juice Cocktail from 1930 is another savory glass without alcohol.

Making it today

We read MacElhone’s spoonfuls as teaspoons and his red pepper as cayenne. Use a pasteurized egg, because the yolk is eaten raw. It is meant to go down in one swallow, yolk and all. Use a small glass, about the size of a sherry glass, so the yolk sits deep in the sauce, and pour the vinegar last and gently, so it runs around the yolk without breaking it. Malt vinegar is MacElhone’s; cider vinegar makes a softer glass.

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Ingredients

For 1 glass. Quantities are shown as written.

Quantities as written here, for 1 glass.

Worcestershire sauce2 metric tsp (5 ml per tsp)
Pasteurized egg1
Cayenne pepper1 pinch
Salt1 pinch
Malt vinegar2 metric tsp (5 ml per tsp)

Ingredients as written here

2 tsp Worcestershire sauce
1 pasteurized egg
1 pinch cayenne pepper
1 pinch salt
2 tsp malt vinegar

Equipment

Small stemmed wine glass or claret glass
Measuring teaspoon

Instructions

Pour the Worcestershire sauce into the glass.
Separate the pasteurized egg and slide the yolk into the glass without breaking it. Keep the white for another use.
Sprinkle the cayenne pepper and the salt over the yolk.
Pour the malt vinegar gently over the top and serve at once, to be drunk in one swallow.

Nutrition

65calories per serving

Recipe makes: 1 glass

Roughly estimated from USDA FoodData Central values for egg yolk, Worcestershire sauce and malt vinegar.

Recipe notes

Notes

Quantities mentioned in these notes don’t change when you adjust the batch.

Changes from the source: MacElhone asks for “a Fresh Egg”; a pasteurized egg is ours, for safety, since the yolk is not cooked. Teaspoons for his “spoonfuls” and cayenne for his “red Pepper” are our readings. Any Worcestershire sauce will do; MacElhone names Lea & Perrins.

Scaling changes the ingredients only; glassware, ice and timings need their own judgment. To adapt this recipe further, try the recipe tool at TuneMyRecipe (opens in a new tab), our sister site.