Oyster Soup
1 quart oysters Sprig of parsley Bit of bay leaf 1/3 cup butter 1/3 cup flour Salt and pepper 1 slice onion 2 stalks celery 2 blades mace Clean and pick over oysters as for Oyster Stew; reserve liquor, add oysters slightly chopped, heat slowly to boilingpoint, and let simmer twenty minutes. Strain through cheesecloth, reheat liquor, and thicken with butter and flour cooked together. Scald milk with onion, celery, mace, parsley, and bay leaf; remove seasonings, and add to oyster liquor. Season with salt and pepper.
This is a strained cream soup rather than a stew: the oysters give up their flavor to the liquor and are then thrown away with the cheesecloth. Read it once through before starting so the loss of the oysters is a decision and not a surprise.
- The hinge: the oysters are a flavoringTwenty minutes of simmering would ruin oysters meant to be eaten, but here they are chopped, cooked down, and strained out to make an oyster essence. If you want oysters in the bowl, poach a second batch separately for two minutes and add them at the end.
- Milk quantityThe liquid measure given for the milk is 4 cups, scalded with the aromatics. With the strained oyster liquor added this gives roughly five cups of finished soup, or four to six servings.
- Blades of maceA blade is a whole piece of the dried aril that wraps a nutmeg. Equivalents vary, but two blades stand in for a small pinch of ground mace; since ground mace cannot be strained out, add it sparingly at the end instead of infusing it.
- ScaldingScalded milk means heated to about 180F, just until a rim of bubbles forms at the edge of the pan. It is hot enough to draw flavor from the onion, celery, and spices without boiling over.
- The rouxEqual parts butter and flour, 1/3 cup each. Cook it two or three minutes until it smells nutty but takes no color, then whisk the hot oyster liquor in gradually to keep it smooth.
- GritThe cheesecloth straining is not optional fussiness. Even after the oysters are picked over, the liquor carries sand and bits of shell, and a doubled layer of cloth or a fine strainer keeps them out of a smooth soup.
- SaltOyster liquor is already saline and reduces further as it simmers. Season only after the milk goes in, or the finished soup will be too salty to rescue.
- Buying oystersA quart of shucked oysters is roughly 40 to 75 depending on size, sold in tubs with their liquor at a fish counter. Keep them refrigerated and use them promptly.
Fannie Merritt Farmer's Boston Cooking-School Cook Book (1896) devotes several consecutive entries to oysters, and the placement is not sentimental: shucked oysters were among the cheapest and most widely distributed proteins in the northeastern United States in the 1890s, shipped inland by rail in tubs of their own liquor. This version sits at the more refined end of the range, since it sacrifices a whole quart of oysters simply to flavor a milk base thickened with a butter-and-flour roux, in the manner of the French cream soups then shaping American cooking-school teaching. The infusion of milk with onion, celery, mace, parsley, and bay is a plain kitchen version of an aromatic milk, and mace, now largely displaced by nutmeg, is often said to have been a characteristic warm spice for oyster and fish dishes in nineteenth-century Anglo-American cookery.