It's like something from Charlie And The Chocolate Factory - a magic berry that sends your taste buds loopy.
Just a pinch makes the sourest lemons sweet, gives vinegar a sherry flavour and turns Granny Smiths into toffee apples.
And East End favourite jellied eels taste like lemonade, even with a coating of chilli vinegar.
The effects are due to a strange natural sweetener known as The Miracle Fruit.
The berries - real name Synsepalum dulcificum - sound like something Roald Dahl dreamed up for his Willy Wonka story, like chewing gum that lasts for ever or ice cream that never melts.
But they have a growing army of fans worldwide.
In Japan, there are restaurants selling vile-sounding dishes like horseradish with lemon peel to giggling diners who scoff the fruit first.
After catching on in America, word has spread to the UK and sales are taking off here.
Some buyers use them to spice up dull dinner parties while others just try them for a laugh.
They've also proved a hit with slimmers craving a sugary snack without the calories. And cancer sufferers are said to use them to disguise a metallic taste that's a side-effect of chemotherapy.
When I first heard about the Miracle Berry I thought it was a wind-up. But the proof was in the tasting.
Bitter lemons and grapefruit tasted like they had a toffee coating. And Guinness was like chocolate milkshake.
The berries let me knock back neat vinegar like it was sweet sherry. And I'm not usually a fan of jellied eels, but they became very tasty.
The red berries from West Africa, about the size of coffee beans, are sold online in a freeze-dried form. In the wild, they grow on bushes up to 20ft high.
The fruit is primarily from Ghana and exported in a sherbert-like form to the UK where it sells for around £2 a gram.
Growers freeze-dry the berries because they lose potency and shrink to the size of raisins if not eaten straight away.
Users simply swirl a small pinch of the powder around their mouths for a minute.
A chemical in the berry called miraculin binds to your tongue's taste buds, making them super-sensitive to sugar.
Fans dub the experience a "legal taste trip" but experiencing it is nothing new.
The wonder berries were first documented by explorer Des Marchais in 1725.
He spotted that natives ate the berry to give their meals a lift.
Food companies have tried to turn the berry into a sweet or chewing gum since the Seventies.
But all failed because US officials classified it as a food additive, which would require years of expensive testing.
Now Brit entrepreneur Chas Barr is flogging it here.
The 28-year-old, from Bromley, South East London, has been selling the product in Europe and around the world since the middle of last year.
The fruit isn't officially recognised under EU food regulations. But Chas expects to get the green light later this year after the necessary research.
He said: "Miracle Fruit has been widely used across many different countries by millions."
"We are leading the appraisal process with the Food Standards Agency to get it classified as safe for human consumption within the EU. We expect it to be classified very soon."