(icing|frosting) on the cake
1
something extra that is added to something that is already good in order to make it perfect
The phrase "icing on the cake" has its origins in the practice of adding a layer of icing or frosting to a cake to make it more appealing or enjoyable. The phrase first appeared in print in the 19th century, and it quickly became a popular idiom for describing something that enhances the enjoyment or value of something that is already good.
- My day was already going well, but when I found out I got the promotion, it was like icing on the cake.
- The dinner was delicious, but the icing on the cake was when the chef sent out a complimentary dessert.
- The party was fun, but when my favorite song came on, it was like the frosting on the cake.