Prune Pie
1 tablespoon lemon juice 1½ teaspoons butter 1 tablespoon flour Wash prunes and soak in enough cold water to cover.
Cook in same water until soft. Remove stones, cut prunes in quarters, and mix with sugar and lemon juice. Reduce liquor to one and one-half tablespoons. Line plate with paste, cover with prunes, pour over liquor, dot over with butter, and dredge with flour. Put on an upper crust and bake in a moderate oven.
Fannie Farmer's prune pie is a cold-weather pie built from stored dried fruit, and the printed ingredient list here is incomplete — the prunes and sugar are missing from the top of the entry.
- The missing quantitiesOnly the lemon juice, butter and flour are given amounts. Comparable prune pies of the period use about 1 lb (roughly 2 to 2½ cups) dried prunes and ½ to ¾ cup sugar for a 9-inch pie; the original figures cannot be recovered from this page, so treat those as reconstruction rather than the book's own measure.
- Moderate oven350 to 375F. A two-crust fruit pie wants 35 to 45 minutes, until the top crust is browned through and the filling bubbles at the vents.
- "Reduce liquor to one and one-half tablespoons"This is the hinge. The prune cooking water must be boiled down almost to a syrup, or the filling floods the bottom crust. One and a half tablespoons is genuinely that little — a glaze, not a sauce.
- Prunes then and nowTurn-of-the-century prunes were generally hard and dry, and usually sold with the stones in, hence the soaking and pitting the recipe calls for. Modern pitted prunes are soft and moist and may need only about 10 minutes of simmering to reach 'soft'; oversoaking turns them to paste.
- Line plate with paste"Plate" is the pie plate and "paste" is pastry — Farmer's plain paste or puff paste from earlier in the chapter. Any standard two-crust short pastry works.
- The flour dredgeA light dusting of flour over the fruit, not a stirred-in thickener. With the liquid already reduced it is there to catch any remaining juice; a scant tablespoon is plenty.
- YieldPresumably one double-crust pie of about nine inches, serving six to eight, though the page states no size or yield. Good barely warm or at room temperature.
Prune pie belongs to the late-winter repertoire of the American pantry, when apples had gone soft and dried fruit was what remained. By the 1890s California orchards around Santa Clara were shipping dried prunes nationwide in quantity, and they became a reliably cheap fruit — which is why a Boston cooking school, teaching thrift as much as technique, put them in the pie chapter alongside apple, mince and squash. The word prune is simply the French prune, plum; in English it narrowed to mean the dried fruit, usually of the Agen-type plum. Farmer's method here, cooking the fruit and reducing its liquid before it ever meets the pastry, reflects the school's general insistence on controlling moisture — the same reasoning behind her precise level measurements, a practice already established at the Boston Cooking School under Mrs. Lincoln before Farmer, though it did much to make her reputation.