Cream the butter and sugar until light. Beat the egg yolks one at a time into the mixture, beating well after each addition. Beat egg whites slightly and add with the flavoring. Beat well.
Sift dry ingredients together twice. Add alternately with the milk to the butter mixture. Beat after each addition. Blend in the caraway seeds.
Pour batter into a greased and lightly floured tube pan. Bake in a 250° oven for 40 minutes, the 35 minutes more at 325 degrees.