Beat the egg yolk and milk together, add the kumala, sugar, salt, butter and lemon rind. Mix very well. Now beat the egg white till stiff and fold into the mixture. Pour into a dish and place this in another dish of water, bake in a medium hot oven until firm.
Another way of cooking it is to pour the mixture into a greased bowl and cover. Put the bowl on top of a saucer placed upside down in a pot which has a good lid. Half fill the pot with water and heat till boiling point. Simmer for about half an hour or till the pudding is firm. Serve cold with cream or lolo.
This mixture also makes a very good pie filling. Just pour it into an unbaked pastry shell and bake. The flavour can be varied by adding vanilla or cinnamon.