Question: why are jaffa cakes in the biscuit aisle?
Answer: McVities defended its classification of Jaffa Cakes as cakes at a VAT tribunal in 1991, against the ruling that Jaffa cakes were biscuits due to their size and shape, and the fact that they were often eaten in place of biscuits. ... The product hardens when stale, in the manner of a cake.