Classic Culinary Arts:

Lemon Sponge Recipe

The juice of four lemons, four eggs, one cupful of sugar, half a package of gelatine, one generous pint of cold water. Soak the gelatine two hours in half a cupful of the water. Squeeze the lemons, and strain the juice on the sugar. Beat the yolks of the eggs and mix them with the remainder of the water. Add the sugar and lemon to this, and cook in the double boiler until it begins to thicken; then add the gelatine. Strain this mixture into a tin basin, which place in a pan of ice water. Beat with the whisk occasionally, until it has cooled, but not hardened. Now add the unbeaten whites of the eggs, and beat all the time until the mixture begins to thicken. Let it thicken almost to the point where it cannot be poured, and then turn into a mould and set away to harden. Remember that the whites of the eggs must be added as soon as the mixture cools, which should be in about six or eight minutes, and that the mixture must be beaten until it begins to harden. The hardening is rapid after it once begins, so that it will be necessary to have the moulds all ready. The sponge will not be smooth and delicate if not poured into the moulds. If for any reason you should get the mixture too hard before pouring, place the basin in another of hot water, and let the sponge melt a little; then beat it up again. Serve with powdered sugar and cream.