Flake is a brand of chocolate bar currently manufactured by Cadbury and consists of thinly folded Dairy Milk, milk chocolate.
The product was first developed in 1920 and was founded by an employee of Cadburys. When the excess from the moulds was drained off, it fell off in a stream and created folded chocolate with flaking properties.
Since 1922 in Britain, Australia and Ireland ice cream vendors serve “99 Flakes” which are vanilla soft serve ice cream in a wafer cone in which a half size Flake bar is inserted in the top. Screwballs are similar but have a plastic cone rather than a wafer.
Info gleaned from Wikipedia