as the icing on the cake, the cherry on the cake, the cherry on top (something that intensifies the appreciation of something already good)
köken: The saying dates back to the times when loaf sugar was widely used. That type of sugar does not dissolve easily, and thus some undissolved sugar often remained at the bottom of a cup of coffee after it was drunk.
Menimme ulos päivälliselle ja tanssimaan ja - sokerina pohjalla - poikaystäväni kosi minua, kun olimme tanssimassa.