Boiled Custard
It is considered better made of the yolks only of the eggs, some whites may be used, however. A dessert spoonful of sugar is enough for each egg, and five yolks are quite sufficient for a quart of milk. Beat the yolks and the sugar together to a froth and stir in the milk; put it into a double boiler. Stir the mixture constantly until it is a little thickened. If it is well stirred, the custard will be a smooth cream; if allowed to remain a few moments too long in the boiling water after it begins to thicken, it will curdle and be spoiled.