Make your own mumma cocktail

Is this 'Swedish Christmas drink' an internet hoax or traditional tipple? This blend of beer and stout may have dubious credentials, but the flavours are fantastic nonetheless
Everyone knows - or they ought to know - that it's a bad idea to believe everything you read on the internet. A friend of mine, a physics professor, has a particularly Machiavellian way of making this point to her students.Every year, the first essay she sets her freshers is on the history of special relativity. Every year, the day before they are due to hand it in, she goes on to the relevant Wikipedia pages and changes a few salient dates and names. She changes them back again the next day, but by then the damage is done: invariably over half the essays handed in contain the inserted falsehoods, parroted as gospel.This week's recipe is also, I suspect, a piece of internet fiction. It was unearthed by Jane Baxter, who works with me on this column. Fed up with mulled wine, she was researching obscure Christmas drinks, and came across mumma - supposedly a traditional and festive Swedish concoction.Alarm bells should have rung. None of her Scandinavian friends had heard of mumma, and the drink - a combination of lager, stout, madeira and gin - sounds ghastly. Furthermore, the few online postings of the recipe read suspiciously like parody. "Exclude all alcoholic ingredients (except the stout)," said one, "and you will have an almost non‑alcoholic mumma."But Jane is a determined culinary explorer. "I made it, and I drank it, and I thought 'this is quite nice'," she says. And it is. In fact, her version - the result ofafter considerable experimentation - is better than that. It's delicious.So, authentic or not, this is what we shall be drinking on Christmas Eve - and, as we do so, we shall raise a glass to Professor Google.

Make your own mumma

Serves 4
500ml lager
500ml stout
250ml lemonade
75ml madeira
A splash of gin (optional)
A pinch of cardamom powder1 Pour everything gently into a large jug. Stir to combine. Serve in large wine or brandy glasses.Recipe by Henry Dimbleby and Jane Baxter. Henry Dimbleby is co-founder of the fast-food restaurant chain Leon (@henry_leon)Photo: Mumma knows best - or does she? A Swedish Christmas drink (possibly). Photograph: Jill Mead for the Guardian