Bring the milk to the boil in a small
pan with the poppy seeds, then remove from the heat, cover and leave
to soak for 30 minutes. Cream together the butter or margarine and
sugar until pale and fluffy. Gradually beat in the egg yolks, then
fold in the flours and baking powder. Stir in the poppy seeds and
milk. Whisk the egg whites until stiff, then fold them into the
mixture using a metal spoon. Spoon into a greased and lined 20 cm/8 in
cake tin (pan) and bake in a preheated oven at 180ºC/350ºF/gas mark 4
for 1 hour until a skewer inserted in the center comes out clean.
Leave to cool in the tin for 10 minutes before turning out to finish
cooling on a wire rack.