Onion Soup
3 tablespoons butter 4 tablespoons flour 1 egg yolk 2 tablespoons Parmesan cheese 1 tablespoon pimento Chop onions, cook in two tablespoons butter five minutes; add water, cook thirty minutes, press through a sieve. Melt remaining butter, add flour, scalded milk, and seasonings, cook five minutes. Combine mixtures, add egg yolks slightly beaten, Parmesan cheese, and pimento. 1 can peas 2 cups cold water 1½ teaspoons salt a bit of bay leaf
This is a cream soup rather than the brothy, bread-and-Gruyère onion soup most people picture: onion purée let down with a butter-flour-milk base and enriched at the end with yolk and cheese. The whole thing hinges on the last step.
- Do not let it boil after the yolk goes inOnce the beaten yolk is stirred into the hot soup, keep the pan below a simmer, around 170–180F. Temper the yolk with a ladle of hot soup first, return it to the pan off the heat, and it will thicken smoothly instead of scrambling.
- Proportions of the white sauceThe recipe splits its butter: two tablespoons go to the onions, leaving one tablespoon to cook with the four tablespoons of flour, so this is a flour-heavy paste rather than an even roux. The scalded milk is not quantified here, so judge by consistency: it should coat a spoon lightly before the onion pur"e9e is added.
- Cooking the onionsFive minutes in butter is meant to soften, not brown. If you want the sweeter, deeper flavour a modern palate expects, give them 15–20 minutes over low heat and stop short of colour, which would muddy the pale finish.
- PimentoPimento here means the sweet red pepper sold canned or jarred, not paprika and not pimento cheese. Drain it and chop it fine.
- ParmesanTwo tablespoons of grated hard cheese is a seasoning, not a body-builder. Add it off the heat with the yolk so it melts without stringing.
- Salt and bayThe ingredient list groups the bay leaf and the 1"bd teaspoons salt with the water for the onions, while the method adds the seasonings to the scalded milk. If you put the bay in with the onions and water, fish it out before sieving, and taste before using all the salt, since the Parmesan brings its own.
- YieldProbably about four small first-course servings, though the milk is unquantified, so this is an estimate.
Lowney's Cook Book was published in 1907 by the Walter M. Lowney Company of Boston, a chocolate manufacturer that, like Rumford, issued a full general cookbook as advertising; the compiler, Maria Willett Howard, is generally said to have worked in the Boston Cooking School tradition of Fannie Farmer, and that tradition's fingerprints are all over this soup. The standard American cream soup of the period was built on a fixed formula — butter and flour cooked together, scalded milk, a vegetable purée stirred in — and the cook simply swapped the vegetable to change the name. The egg yolk and grated cheese are a French-derived liaison, a finishing enrichment; the chopped pimento was a fashionable garnish in the first decades of the twentieth century, a period when canned Spanish sweet peppers are often said to have become widely available in American groceries.