The teaser for the new episodes shows a young boy carrying precious cargo in his backpack as he cycles through streets, past people desperate to get their hands on the rare commodity.
Viewers see a man begging a pizza chef at the back door of his restaurant, while neighbours share rumours over the garden fence and an older woman taps out an imploring text message.
Eventually it is revealed that the woman is the boy’s grandmother and he presents her with the bag of flour he has been transporting.
The trailer shows them tucking into a huge cake, emblazoned with the words “Bake Off’s Back”.
Production of the 11th series was initially delayed because of the coronavirus pandemic, but filming on the popular show finished last week.
Zaid Al-Qassab, chief marketing officer at Channel 4, said: “This year’s Great British Bake Off campaign highlights that baking is about so much more than sustenance – it’s a gift.
“The film illustrates the nation’s joyous love of baking, inspired by our shared experience of lockdown in a typically Channel 4 way, and we hope it gets viewers as excited as we are for the return of our biggest show!”
The wider marketing campaign features the Bake Off tea-towel, illustrated by Barry Falls, and showcases dramatic scenes from the show, including Ruby’s collapsing vegan cake, a Hollywood handshake, and the Bake Off squirrel.
The trailer will debut on Channel 4 at 9pm on Tuesday.
It was previously confirmed that the show will look as it always does when it returns to screens due to the cast and crew living and filming “in a bubble”.
Kelly Webb-Lamb, deputy director of programmes and head of popular factual for Channel 4, said during a controller session at Edinburgh’s Television Festival that the “enormous” feat of getting the show back on air was accomplished due to stringent health and safety measures, testing and quarantine regimes.
In the forthcoming series, comedian Matt Lucas replaces Sandi Toksvig as the programme’s co-host alongside Noel Fielding.
The duo join judges Prue Leith and Paul Hollywood.