Blancmange is a dessert made of milk, sugar, and sometimes almonds. It’s usually served cold in a mold. It’s kind of like vanilla pudding. For some reason, it’s often pink.
This French term means "white food," and that's a very good description of blancmange. This dessert is like a pudding made from milk and cornstarch, and although it's sometimes pink, it's usually white and somewhat bland. However, there are various ways of livening it up. Sometimes spices or even shredded chicken is added. Occasionally, this word has been a synonym for nonsense, as in, "That's a load of blancmange!"