Sieve the flour, salt and baking powder into a bowl, and rub in 6 tablespoons butter or lard until free from lumps. Pick and clean the sultanas, and add them with the sugar, candied peel and vanilla extract. Make a well in the centre, add the well-beaten eggs, and then gradually mix in the milk. Mix together thoroughly. Put the mixture in a well-buttered cake tin, and bake in a moderate oven (375°F-M4) for about 30 minutes, or until well risen and firm to the touch.
To serve: cut into squares, sprinkle with additional sugar and serve hot with cream.