I create M&S Christmas foods – the motto we follow to make tasty £9 turkey lasagne that customers want to buy

But just how do their food team come out with such innovative and fresh ideas, year-on-year?

Apparently there is one golden rule that the Marks and Spencer product development team has to follow.

And head of the team, Stephen Fitzgerald, clued in to the guidelines they have to follow when coming up with new and exciting Christmas products.

Stephen said: "‘There has to be a balance around Christmas because it’s such a nostalgic time of year in terms of food and tradition, but at the same time, people want novelty and they want something different and interesting.

"You can’t make something too tricksy, so we have a motto which is that you can change one thing, but don’t change two. 

"If you change too much, customers can become a little bit frightened, so we kind of take them by the hand and coax them into change."

One of the stand-out examples of this rule is Marks' new Turkey Feast Lasagne.

The spin on traditional Italian is reminiscent of the retailer's iconic , which shoppers run back for every Christmas.

When launching the lasagne, Marks and Spencer said , it's 'perfect for diving into over the next few weeks to keep those Christmas dinner cravings at bay before the big day!'

And the comments were full of people eager to try the latest offering, with one writing: "That does look nice."

And another saying: "Well hello there."

The dish has a delicious slow-cooked turkey ragu, sausagemeat and cranberry stuffing, layered between thick egg pasta sheets and bechamel sauce.

Stephen said the choice to swap turkey into the recipe over traditional beef was an example of knowing the limits of what to experiment with: "People love lasagne, so what we’ve done is put a bit of a twist on the classic. We changed the meat and added all the elements of our Turkey Feast sandwich, but kept the familiar format. 

"I’m sure there are Nonnas in Italy who would be absolutely appalled by it, but it’s resonating with customers."

And the lasagne has been praised by hundreds of positive review videos and comments on .

It's been dubbed 'full of flavour' and 'absolutely amazing' by users of the video platform.

So, did the Marks and Spencer product team know they were creating such a viral hit?

Stephen said: "We definitely have an informed view, whether that’s from market research or customer insights – it’s a heavily educated guess.

"At the same time there’s always an element to it that when [a new product] worries you a little bit, that’s probably quite a good thing, it’s quite healthy. If it’s going to be a safe bet then anyone could do that. It’s when you get a little bit of fear, then you realise you might be on to an absolute winner, and that’s what we like to do. We like to push boundaries and thankfully we get it right more often than we don’t."

And how does Stephen feel about holding the creative reigns of the product development team at such an iconic British supermarket?

"‘I have one of the best  in the world.