In February 2015, the Great British Bake Off ruffled a few feathers when it introduced a new kind of celebrity to its charity special.

The Great Comic Relief Bake Off - as it was when still in the hands of the BBC - had just shown Joanna Lumley, Jennifer Saunders, Lulu and Dame Edna battling it out to be crowned Star Baker.

But alongside well-known celebs Gok Wan, Jonathan Ross, model and TV star Abbey Clancy, the BBC threw in a wildcard: the YouTube star Zoella.

Reaction ranged from bewildered to downright confused: why was a YouTuber best-known for makeup tutorials and showing off shopping hauls considered famous enough to appear on one of Britain's most beloved TV competitions?

'My parents r in the other room watching British bake off and I can just hear them saying 'I don't get youtube' 'what is zoella?,' wrote one user on Twitter. 'Watching The Great Comic Relief Bake Off & I still have no idea what the f*** a Zoella is,' added another, less diplomatic, viewer.