Put ingredients into a smooth granite stewpan. Stir, place on range, and heat gradually to boiling point. Boil without stirring until, when tried in cold water, a soft ball may be formed that will just keep in shape, which is 238 °F. After a few minutes’ boiling, sugar will adhere to sides of kettle; this should be washed off with the hand first dipped in cold water. Have a pan of cold water near at hand, dip hand in cold water, then quickly wash off a small part of the sugar with tips of fingers, and repeat until all sugar adhering to side of saucepan is removed. If this is quickly done, there is no danger of burning the fingers. Pour slowly on a slightly oiled marble slab. Let stand a few minutes to cool, but not long enough to become hard around the edge. Scrape fondant with chopping knife to one end of marble, and work with a wooden spatula until white and creamy. It will quickly change from this consistency, and begin to lump, when it should be kneaded with, the hands until perfectly smooth.
Put into a bowl, cover with oiled paper to exclude air, that a crust may not form on top, and let stand twenty-four hours. A large oiled platter and wooden spoon may be used in place of marble slab and spatula. Always make fondant on a clear day, as a damp, heavy atmosphere has an unfavorable effect on the boiling of sugar.