Classic Culinary Arts:

Blanc Mange Made With Isinglass Recipe

One quart of milk, three and a half sheets of Cooper's isinglass, half a teaspoonful of salt, three table-spoonfuls of sugar and a four-inch piece of stick cinnamon. Break up the isinglass, put it and the cinnamon with the milk, and let stand in a cold place two hours; then put it in the double boiler and let it come, gradually, to the boiling point. It must not boil. Stir often while heating. As soon as the isinglass is dissolved, take from the fire, and add the salt and sugar. Strain into a tin basin, which place in a pan of cold water. Stir occasionally while cooling. When nearly cold, turn into a mould and place in the ice chest. It can be poured into the mould as soon as strained, but the cream will rise to the top in that case, unless the mixture is stirred carefully in the centre of the mould. The sheets of isinglass vary in thickness, so that it is best to take part of die thick sheets and part of the thin.