Sift together the flour, salt and baking-powder. Rub in the fat. Add the sugar and cocoa; mix well. Add the beaten egg and milk and mix to a dropping consistency. Add the vanilla essence. Put into a greased tin or pie-dish. Bake in a fairly hot oven (375° F., Gas 5) for 30–40 min.
Dredge well with castor sugar and serve with chocolate or custard sauce.