Tomato Bisque
Cook together 1/2 tablespoonful of butter and 1 scant tablespoonful of flour. Stir in slowly 1 1/4 cupfuls of hot milk; when smooth and thick, season well with salt and pepper. When ready to take from the fire add 1/3 of a cupful of hot strained tomato, to which a tiny pinch of baking soda has been added. Do not heat again, or it will curdle.
A single-serving cream soup built on a small white sauce, with the tomato added off the heat at the last moment. The whole thing takes under ten minutes once the tomato is strained.
- The hingeAcid plus hot milk equals curdling. The tomato goes in after the pan leaves the burner and the soup is served immediately; reheating undoes it, exactly as the recipe warns.
- An ambiguous measurement"1/4 cupfuls" is probably a typesetting slip; the plural suggests a dropped figure such as "1 1/4," and "stir in slowly" reads oddly for so little liquid. Half a tablespoon of butter and a scant tablespoon of flour will thicken well over a quarter cup of milk, so treat the printed figure as uncertain and go by consistency -- the recipe wants it "smooth and thick."
- The baking sodaA tiny pinch neutralises part of the tomato's acid so the milk is less likely to break. A pinch means a pinch — too much gives a soapy, flat taste and a dull brownish colour.
- Strained tomatoIn 1900s cookbooks this means stewed fresh tomatoes or canned tomatoes pushed through a sieve to remove skin and seed. Plain canned tomato purée or passata is the direct modern equivalent; avoid seasoned pasta sauce.
- Cook the flour"Cook together" means letting the butter and flour bubble for a minute before the milk goes in, long enough to lose the raw taste without colouring.
- YieldSmall: three-quarters of a cup if the printed 1/4 cup of milk is taken literally, closer to 1 3/4 cups if the milk figure is the suspected 1 1/4 cups. Either way it is one to two bowls.
Tomato bisque of this kind belongs to the economical American soup repertoire of the late nineteenth and early twentieth centuries, when canned tomatoes became cheap and reliable and a white sauce could stretch a little milk into a course. Bisque properly meant a thick shellfish soup finished with cream, but American cookbooks came to apply the word to any sieved, cream-enriched purée, tomato most of all. The baking soda trick appears in book after book of the period and reflects a real limitation: acid tomato and hot milk separate on contact. Butter, flour, milk and a spoonful of tomato made a hot first course out of almost nothing.