The bars combine Cadbury Dairy Milk chocolate with two mystery-flavoured fillings and the shopper who guesses the flavour correctly will win a mystery prize, worth £5,000.
Shoppers can enter the competition by visiting mysterybars.cadbury.co.uk or by scanning the QR code on-pack.
The promotion is being supported by in-store support, digital, outdoor, social media, audio and PR advertising.
Pippa Rodgers, brand manager for Cadbury Dairy Milk at Mondelez, said: “Cadbury Mystery Bars is the latest in a stream of highly impactful consumer activations from the nation’s favourite chocolate brand.
“We are excited to launch this new competition from Cadbury Dairy Milk and challenge the nation to solve the flavours of Cadbury Mystery Bars.”
Each flavour is available now in 43g single bars and 170g tablets until October.
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