From the Ladies' Page, The Illustrated London News, 4th September 1915.
As we are looking in every direction for food economies, we may utilise pumpkins, which are just now abundant, and often allowed to go to waste. American pumpkin pie consists of two thin layers of pastry with the stewed gourd, mashed, sweetened and flavoured with cinnamon or ground mixed spice, as a central layer. More acceptable to many will be pumpkin soup (potage de potiron). The French flavour this soup either with salt and a touch of cayenne pepper, or with sugar, according to the taste of the diner, just as they do melon eaten raw at the beginning of dinner. The followers of the sugar idea declare that pumpkin soup is infinitely better lightly sweetened than salted; but both ways should be sampled. The potage is simply made. A slice of ripe, juicy pumpkin, weighing about a pound when cut off the rind, is simmered till soft in a little water very slightly salted; it needs but ten minutes or so, stirring frequently. It is then strained from any superfluous water and mashed, either through a colander or a wire sieve, and returned to the pan with two ounces of butter, which is to be stirred well up; pour in and mix, stirring all the time, a pint of boiling milk; then pour immediately into the tureen, in which is sliced up half a French roll; or, if that is not available, have some dice of bread fried crisp in butter or dripping to hand with the soup. A little sugar or a little salt is added in the soup-plate at the diner's option, but it should be very little of either, or the delicate flavour is lost. Vegetable marrow soup can be made in the same way. Onion, celery seed, or parsley and sweet herbs can be added at different times to make variety. Pumpkins are also most accommodating in taking the flavour of anything cooked with them, and so can be mixed with plums or apples in an ordinary English fruit tart or pudding when the fruit is scarce; or boiled in the ordinary way with fruit for jam will produce good results.
[Food economy was becoming an urgent concern - and food shortages would become much more serious before the war was over. I don't think that eating pumpkin is the answer to food shortages - there are very few calories in it. But for people who still felt that dinner should have multiple courses, and didn't need the calories, pumpkin soup might be a good economy.]