The “recipe for great food” campaign features both chefs in a faux-documentary style television ad.
The activity, which also includes press and online, uses the strapline: “Everyone’s recipe for a great Christmas”.
Smith demonstrates how to make her classic Christmas cake while Heston creates his hidden orange Christmas pudding.
Waitrose has also created a “prepared ingredients pack” which includes all the ingredients to help shoppers make Smith’s 40-year old Christmas cake recipe.
The campaign is split into two parts, one featuring Smith under the “bake” banner and the other featuring Heston and the “Heston for Waitrose” Christmas range under the “treat” banner.
As part of its festive offers, Waitrose is also running a half price promotion on mince pies, port and cream, promoted through press ads.
Morrisons has launched a Christmas ad focusing on its fresh produce message, while Asda’s festive campaign focuses on its Extra Special food range.
Tesco’s Christmas ads feature Britain’s Got Talent judge Amanda Holden.
Sainsbury’s has yet to reveal its Christmas campaign.