Sour-Milk Gingerbread

A large, plain molasses gingerbread of the kind mixed in one bowl and baked in a sheet. The recipe assumes you know the method, so the notes below fill in vessel, temperature and the few terms that have shifted.

• Sour milkThis means naturally soured raw milk, thick and acidic. Cultured buttermilk is the direct modern stand-in; failing that, stir 1 tablespoon lemon juice or white vinegar into a cup of whole milk and let it stand ten minutes. The acid is not optional flavouring — it is what the 2 teaspoons of soda react with.
• ShorteningThe word covers lard or butter, and in later years hydrogenated vegetable fat as well. A cup of butter gives good flavour; if you use lard, the recipe's own instruction to add a teaspoonful of salt applies, since lard is unsalted.
• Lemon"1 teaspoonful lemon" means lemon extract, sold alongside vanilla. Grated zest of one lemon is a fair substitute and rather better.
• The cinnamon is unmeasuredThe line reads "1 teaspoonful lemon, and cinnamon," which most likely intends a teaspoon of each, but the original does not say so outright. A teaspoon of cinnamon against a tablespoon of ginger is a sensible balance for this quantity of batter.
• OvenThe recipe gives no oven direction; a moderate oven, around 350F, is a reasonable modern setting. Gingerbreads with this much molasses and sugar are apt to scorch on the bottom before the centre sets if pushed hotter.
• Pan and timeThe batter fills a 9-by-13-inch pan generously, greased and floured, and takes about 40 to 45 minutes; a skewer should come out with a few moist crumbs. Two 8-inch square pans at 30 to 35 minutes also work.
• Mixing orderCream the fat with the sugar, beat in the eggs and molasses, then add the flour and spices alternately with the sour milk. Dissolve or sift the soda in last and get the batter into the pan promptly — the rise begins the moment acid meets alkali.
• YieldAbout 20 squares. It keeps well wrapped for three or four days and improves on the second day, as most molasses cakes do.