Nestlé is launching luxury KitKats costing up to £14 a bar that will be available to buy from a bespoke website and at pop-up stores.
It represents the first-ever move into direct-to-consumer by Nestlé's UK confectionery business.
The initiative, which Nestlé has branded Chocolatory, also includes a tie-up with 30 John Lewis & Partners stores and the Chocolate Story museum in York.
At the flagship John Lewis store on Oxford Street, the retailer will offer visitors the opportunity to create their own bespoke KitKat at a 2,000sq ft pop-up. KitKat will also run a pop-up in the John Lewis store at the Trafford Centre in Manchester.
Rabia Khan, head of KitKat Chocolatory at Nestlé UK and Ireland, describes the move as the biggest news for KitKat since the launch of its Chunky variant 20 years ago.
The bars will be available to buy in store later this week and from the Nestlé online shop in November. Personalisation options include bespoke packaging and the ability to choose flavours.
The eight-chocolate-finger "create your break" option offers almost 1,500 variants. Shoppers can choose from four chocolate varieties and a range of ingredients such as shortbread pieces, salted caramel chunks, honeycomb and rose petals.
Chocolatory will also include "best of British" flavours exclusive to John Lewis, including Eton mess, cherry Bakewell and marmalade.
Khan said: "We know how much people enjoy experimenting with new and exciting KitKat flavours and the KitKat Chocolatory offers a whole new, premium KitKat experience, as well as the chance to create your very own personalised break and have it delivered right to your door."
KitKat is Nestlé’s biggest brand and was invented in York in 1935, when it was first introduced as Rowntree’s Chocolate Crisp before being rebranded as KitKat a couple of years later.