Fondant
1 teaspoon cream of tartar flavoring Boil sugar and water until a soft ball can be formed. Wash sides of saucepan with moist cheese cloth, as fast as the sugar crystallizes. Pour on to marble. When it begins to harden, work with a spatula until creamy.
Chill, flavor, melt, and use for frosting. 4 egg whites
A basic poured fondant, worked on stone in the old confectioner's manner. The method is sound; the proportions as printed are incomplete, so treat the quantities below as the ones to settle before you start.
- Missing proportionsThe ingredient line gives only the cream of tartar and flavoring — the weights of sugar and water are absent, so no conversion can honestly be supplied. Fondant recipes of this kind commonly used something on the order of 2 pounds sugar to 1 cup water; against that scale a full teaspoon of cream of tartar is a large quantity, and more acid means a softer, slower-setting cream. Without the printed weights this is guesswork.
- "Soft ball"238–240F on a candy thermometer. The cold-water test is what the book intends: a drop pressed between the fingers in ice water holds a ball that flattens when released.
- The hinge — do not stirOnce the syrup boils, leave it alone. A single stray crystal dragged back into the pan seeds the whole batch coarse. That is the entire point of the damp cheesecloth wiped around the pan sides.
- Marble, and what to use insteadA marble slab draws heat out fast and evenly. A heavy granite countertop, a large glass baking dish inverted, or a chilled sheet pan will serve. Rinse it with cold water and dry it first; do not grease it.
- When to work itLet the poured syrup fall to about 110F — lukewarm to the back of the hand, with a skin beginning to form — before you take the spatula to it. Working it hot gives grainy fondant.
- Chill, then flavorThe ripening step is real: wrapped tightly and rested a day or more in the refrigerator, fondant becomes markedly smoother and easier to handle. Flavoring goes in after ripening because heat and time drive off volatile oils and extracts.
- Melting for frostingWarm it in a bowl set over hot, not boiling, water, thinning with a teaspoon of water or cream at a time. Above roughly 140F it loses its gloss and sets dull and hard.
- YieldThe recipe gives no quantities, so no yield can be stated. As a rough guide, two pounds of sugar would give enough fondant to ice two 9-inch layer cakes, or to make several dozen centers for dipping.
Fondant — from the French fondre, to melt — is the confectioner's foundation stock, the thing from which bonbon centers, dipped creams, mints and poured cake icings are all built. Its spread through nineteenth-century American candy kitchens is generally traced to cheap refined sugar and to the marble slab, which let a worker crash-cool syrup evenly enough to control crystal size by hand. The cream of tartar does chemical work: in hot syrup it inverts part of the sucrose into glucose and fructose, which interfere with crystal growth and give the finished cream its fine, short texture rather than a gritty one. Lowney's was a Boston chocolate house, and a book issued under its name treats fondant as a household skill rather than a trade secret.