Raised Biscuit
Grate four cold boiled potatoes, put into a quart of hot milk (not boiling). When cool, add butter the size of an egg, four teaspoonfuls sugar, one teaspoonful of salt, one half cup of yeast. Stir in flour to make a sponge; when light, mold and put in tins. When light again, bake in a moderate oven.
A potato-enriched yeast dough of the kind that stood in for baking-powder biscuits when the family kept its own yeast. The recipe assumes you know what a sponge is and gives no flour weight, so the quantities below are the ones worth pinning down.
- Milk temperature is the hinge"Hot milk (not boiling)" means scalded, and the instruction to wait until it is cool is not optional. Add the yeast only when the mixture is around 100-110F; hotter and you kill it.
- The yeastHalf a cup means liquid homemade yeast or barm. Two packets (about 4 1/2 teaspoonfuls) of active dry or instant yeast is a workable substitute, though the flavour will be cleaner and the rise faster.
- Butter the size of an eggUsually taken as about 2 ounces, or 4 tablespoons. Nineteenth-century books often used the egg as a volume gauge, though the measure was only ever approximate.
- Flour is unmeasured"Stir in flour to make a sponge" then more to mold means a batter first, stiff dough second. For a quart of milk expect somewhere near 3 pounds of flour in total, but add it by feel: soft, slightly tacky, not stiff.
- The potatoesFour cold boiled potatoes is perhaps a pound. Grated cooked potato holds moisture, which is why these biscuits tend to stay soft longer than plain ones. Russets or any floury potato work best; waxy ones grate into gluey shreds.
- Two rises, both to the eye"When light" is the only timing given. The sponge wants to be foaming and domed, an hour or so with modern yeast; the shaped biscuits want to be visibly puffed and slow to spring back, 45 minutes to an hour.
- Moderate oven350 to 375F. Twenty to twenty-five minutes for biscuits set close together in a tin, until the tops are deep gold and the sides have knit together.
- YieldA quart of milk is a large batch by modern standards, around three dozen biscuits. Halving it works without adjustment.
Potato in bread dough was a common practice long before commercial yeast made rising dependable. A household yeast kept in a jug was erratic, and the starch and moisture in cooked potato gave it something easy to work on while keeping the crumb soft and slowing staling, which mattered when baking day came once or twice a week. "Raised biscuit" distinguishes the thing from the chemically leavened biscuit that was overtaking American tables by 1900 as saleratus and then baking powder became cheap and reliable; the older raised sort is often said to survive in the parker house roll and in the potato rolls still sold at Thanksgiving.