It is Snoop Dog’s favourite biscuit, has an ice cream flavour, appears in countless TikToke recipes, and is about to collaborate with Cadbury’s, launching in Tesco very soon.

But it all began in a small factory in the little town of Lembeke in Belgium which has been quietly baking away for nearly a century until last year when its revenue topped £1 billion.

Only five people in the world know the secret recipe for this particular little biscuit, but millions know they like it. Net profits were up 19% to almost 156 million euros (£130 million) as the biscuit once known for being given out free at the hairdressers with your cup of tea enjoys new global popularity.

We are talking about Biscoff, which is apparently Gen Z’s favourite biscuit. Snoop Dog is also known to be rather partial and has declared himself a fan, to the delight of the company.

The biscuits, whether they end up in packs or individually wrapped, are now made at a rate of more than 20 million a day, in factories in Belgium and the US. Sainsbury’s sells them at £1.70 for 16 — at 69p/100g.

The story of Biscoff begins with the Boone family, according to The Times. Little Jan was about seven when he sneaked out of his home in Lembeke — a small Belgian town just north of Ghent — to raid his family’s biscuit factory.

“I loved to eat the raw dough,” Boone, who is now 53, said.

It was his grandfather, also called Jan, who had devised the still-secret recipe for the biscuits, which he called Lotus, in 1932.

They were speculoos, a simplified version of speculaas, the spiced festive treats that have been revered for centuries in Belgium and the Netherlands.

Lotus speculoos were marketed as an accompaniment to coffee. Jan remembers travelling as a teenager to the US with his Uncle Karel Boone in the mid-1980s. Lotus had struck a deal to supply its speculoos to an airline as an in-flight snack under a new name: Biscoff, a combination of “biscuit” and “coffee”.

Forty years later, the fourth Boone to run Lotus — Jan took over from his father, Matthieu, Karel’s brother, in 2011.

He has transformed the freebie biccy handed out by airlines, hairdressers and cafés into a gigantic global snacking success story.

Food influencers on TikTok and Instagram cook up viral Biscoff “hacks” and recipes for tiramisus, cakes, milkshakes, mousses and blondies.

Ice cream sellers roll your scoop in Biscoff crumbs. There are Krispy Kreme Biscoff doughnuts and a Lotus Biscoff McFlurry.

Then there are Biscoff-flecked Milkybars, KitKats, and apparently, there will soon be Cadbury products.

So what’s in it that makes it so special? Well there’s a small amount of cinnamon in Biscoff but the principal caramel flavour comes from kandij sugar, a Belgian confection made by heating white beet sugar.

The biscuits are crumbly and very sweet, containing 3g sugar per 8g biscuit which is more than twice the proportion of sugar in a digestive.

The company has 3,000 employees and 12 production sites around the world making dozens of other baked goods. Two plants are dedicated to Biscoff — one opened in North Carolina in the US in 2019 — and a third is due to be fired up in Thailand in 2026. The company’s share price has quadrupled in the past five years.

Biscoff’s success is partly due to the younger generation’s obsession with coffee, but those in the business say social media has had a huge hand in its recent growth spike by including the biscuit in so many online recipes.

“It has helped build up this huge brand loyalty on social media that has given Lotus the power to push out into new areas” said Ben Roberts at License Global, which analyses brand licensing and partnerships.

Boone said he’s not worried about his Biscoff empire crumbling. “We want to conquer the world” he said.