M&S is set to launch its own version of the viral “Dubai-style” chocolate bar – but there's a huge twist.

That's because the chocolate is actually an update on the supermarket's that had shoppers going wild last year.

Chocolate bars with caramel and a green filling.The new Big Daddy Pistachio will be available at M&S from April 23Illustration of a whale on a chocolate bar wrapper; "The Big Daddy" chunky chocolate bar with caramel, peanut butter & roasted peanut pieces.M&S' original Big Daddy Chocolate Bar is very popular

Just like the original Big Daddy, the new bar has layers of thick milk chocolate, gooey sweet and salty caramel and a light and crunchy biscuit crumb.

But it's now got a new chunky pistachio layer made with real roasted pistachios, pistachio crème and white chocolate.

The sweet treat will be available in M&S Foodhalls from April 23.

That means shoppers will have to wait a while to get their hands on the snack – but M&S promises it's worth the wait.

It says the bar was developed over nine months “to ensure absolute perfection”.

The original Big Daddy was priced at £6.75 for a 300g bar which served 10 people.

at the time said it was the “best chocolate bar” and that it was “so good”.

The Big Daddy Pistachio will cost £8.50 for a big 280g bar.

While it's not cheap, it is still less costly than the original “ chocolate” it's based on.

The original was created in Dubai by the Fix Dessert Chocolatier, and can cost up to around £20 for a huge tablet of chocolate filled with pistachio cream and kunafa.

Since the tasty treat went viral, retailers have been launching and .

M&S director of product development Kathryn Turner said: “We've seen the pistachio trend explode in the past few months, both on restaurant menus and on social media, so it's a real focus for us as one of our top flavour this year.

“For example, our new was flying off the shelves well over a month before Easter, while shoppers were snapping up 5,000 jars a day of our top-quality Collection Pistachio Crème when it launched – that's 7 jars every minute.

“In fact the pistachio creme has been so popular that we're now bringing it back all year round!”

She also teased that M&S has even more “exciting pistachio launches” in its stores for the and beyond.

This includes chocolate, cookies, desserts and even a Pistachio and Honey Baking Feta.

Other supermarkets that have jumped on the pistachio trend include , which had shoppers queuing outside its stores to try nabbing one of the £3.99 J.D.Gross Dubai Style Chocolate bars.

Meanwhile has been selling larger 100g bars of Bolci Dubai-style chocolate for just £5.

The bar is available online but you'll have to pay a delivery charge.

Those happy to spend a bit more can try Lindt's Dubai-style chocolate.

It's on sale at , and direct off the Lindt website for £10.