Complementary icing on cake does indeed do wonders. In our family you always got to choose what kind of cake you wanted for your birthday. My brothers and I always chose dark chocolate with peanut butter icing. PB icing is made by adding smooth peanut butter to vanilla butter cream icing.

Then there is one of my favorites, which is maybe not exactly 'icing' - gingerbread covered with whipped cream, sweetened and flavored with finely grated orange zest.

Pardon my perpetuating a food thread.