Sales of Waitrose’s Yumdough have been “unprecedented”, according to the retailer.

Having launched the bakery hybrid, the combination of a yum yum and a doughnut, which is available at 40 stores this month, Waitrose has reported that the butterscotch flavour has sold out nearly every day since its launch, fuelled by commentary on Twitter.

Alice Beverton Palmer, web editor for Women’s Health UK, tweeted: “Oh @waitrose, you know how to make a girl happy. The vanilla and raspberry Yumdough lives up to its name!”

Jessica Kirby, junior account executive at Cirkle PR, said: “It’s all about the Yumdough now - you’ve got to try one! .

Commenting on the success of the product, Tim Stevens, Waitrose patisserie buyer, said: “The launch of the Waitrose Yumdough has certainly caused a stir with our shoppers, with many rushing to our shops to get hold of the sought-after sweet treat. We knew they’d be popular, but over the past week sales of the Yumdoughs have been unprecedented.

“The most popular flavour is butterscotch, and we have sold out nearly every day since last Tuesday. There has also been a great buzz about Yumdoughs on Twitter, which has certainly added to their popularity.

Each Yumdough is made from dough, which has 144 layers, topped with sugar icing with pockets of filling and fondant. It is available in four flavours: chocolate & orange, lemon, butterscotch and raspberry & vanilla.

Elsewhere, Greggs has increased production of its Greggsnut by 400% due to “overwhelming public demand”.