Kit Kats are made of Kit Kats. The
manufacturers leave no Kit Kat uneaten,
so every reject is mashed into a paste
that’s used to fill the wafers. Because
every imperfect Kit Kat was already filled
with other imperfect Kit Kats, and some
of the Kit Kats they’ll fill will also be
rejected, every time you eat a Kit Kat,
you’re basically eating layers of Kit Kats
within Kit Kats within Kit Kats. Source
It’s Kit Kats all the way down