Boiled Custard
(from Joy of Cooking)

4 C milk, scalded
4 egg yolks
1/2 C sugar
1/4 tsp salt

In a double boiler, slowly add the slightly beaten egg yolks to the warm milk. Stir in the sugar and salt. Cook the custard over (not in) boiling water, stirring constantly. The custard should not be allowed to boil at any time. Do not expect it to be as firm as baked custard. It is more like a thick custard sauce. Again stir constantly until it begins to thicken. This takes longer than one would like. Remove from heat. As it cools, beat to release the steam. Before chilling, add flavoring, such as 1 tsp vanilla ( or rum or dry sherry).