If you’ve ever read a review of a Spanish restaurant, then you’ll think you know the origin of tapas already. You will have been told, many times, that bartenders in Spain were wont to put little plates on top of drinks when they served them, to keep the flies off (“tapa” meaning, literally, “lid”). That they thought this looked a little bleak, and so started putting a few olives on. An anchovy here and there. A slice of ham. Sautéed chorizo. A giant paella with a pig’s head in it. Until a tradition developed whereby a drink always came with a free little morsel.

Hispanophiles then usually go on to lament the modern habit of paying for tapas, and then they’re into the long passage about how tapas bars only work where there are a lot of them to walk between, where the weather is warmer and the licensing laws looser, where people are not enslaved to the ritual of the formal meal, where the natives have afición for this and a pasión for that, where the bulls are nobile and the girls are cha cha cha, until you want to prick them with a million cocktail sticks and watch them die screaming.

And it turns out it’s all rubbish. That is not how tapas started at all. I know this because my mate Bob is a doctor of tapas. He really is. He completed a PhD a few years back entitled Food, Art and Literature in Early Modern Spain – Cultural Representations of Food in Velasquez’ Bodegones, Guzman de Alfaracha, Don Quixote and the Still-Life Paintings of Sanchez Cotan (2001). He is the Schama of chorizo, is Bob. The Starkey of Serrano ham, the A. J. P. Taylor of tapas.

And he says there is a chapter in his thesis which turns tapas theory on its head. Its genesis, he says, is purely commercial. And I will tell you how it worked, very briefly, so that next time someone gives you the fly theory you can talk the tits off them right back.

Basically, says Bob, the sale of food and alcohol together was prohibited in early modern Seville by city authorities who believed that hunger would force potentially errant husbands back to their wives. Bar owners were allowed to provide tablecloths, bread and salt, as well as a small stove. Nothing more. So what people tended to do was to get a round in, and then nip across the road for some prawns or sausage or something from a nearby stall, which they would bring back to prepare and eat with their fino, manzanilla, cerveza, whatever.

The next stage of the process, the employment of a third party to prepare the food, is pinned down by Bob to a very specific moment in the early 17th century (I’m not making this up), which he backs up with reference to a novella by Cervantes, Rinconete y Cortadillo, in which the two young protagonists are advised that they can easily make a living by selling and cooking food in taverns for drinkers.

From here developed the principle of a rolling meal of little bits and pieces. Yes, it is possible that the small plates were then used to cover drinks (though you’d only be feeding your food to the flies instead of your drink) – but it developed that way round, and not t’other.

No doubt you are now impatient to share this information with the world, to lay waste the bastions of tapasial ignorance. But how to get it into the conversation? Well, I suggest you take your foodie pals to Barrafina. That’s where I took Bob, and that is where the subject must inevitably arise.

For Barrafina is a tapas bar, and the best of its kind I ever saw. I wouldn’t normally take Bob to a Spanish restaurant in London. He has spent half his life in Spain, and London’s pale imitations of its food tend to distress him. And to be fair, I have never in my life eaten more consistently well than on trips with Bob to Seville, Granada, Jerez and Madrid.

But Barrafina is owned by Sam and Eddie Hart, owners of Fino, the best Spanish restaurant in England, and I had every confidence. Sam and Eddie share Bob’s passions with equal fire, but turn them into restaurants rather than theses. Both of which are necessary to make the world go round.

Bob was impressed. And that is a rare thing. For the place looks and feels, despite a very English Soho media clientele, totally Spanish. And the food is fantastic.

It’s at the top end of Frith Street, one of London’s hottest food streets these days. Small room, big window; corner bar, 27 stools, lots of staff behind the counter pouring drinks, frying, grilling, shelling; nice ceramic Cruzcampo tap, frozen glasses, beer brewed in Seville, not, like San Miguel, in Manchester. Opens at noon, full to bursting by quarter past.

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