I avoided tax yesterday, and bought the chocolate bar on the right.

Chocolate bars sold to eat: 20% VAT
Chocolate bars sold for cooking: 0% VAT

Even if exactly the same chocolate.

VFOOD6180 - Excepted items: Confectionery: The bounds of confectionery, sweets, chocolates, chocolate biscuits, cakes and biscuits: The borderline between confectionery and zero-rated food - HMRC internal manual - GOV.UK

@danneidle tell me more about this chocolate body paint.