Mr Norgrove, who was involved in the official campaign to leave the EU, seeks to present himself as one of the many voices of reason and moderation in the debate around Brexit. In this he has much in common with ‘liberal leavers’ and ‘Flexciteers’ like the Norths (père et fils), Roland Smith and all those who favour moving to EFTA/EEA membership, either permanently or as transition. There is overlap, too, with those ‘Remainers’ — like Stephen Kinnock MP — who rather than being consumed with impotent rage about Brexit (cf. Chuka Umunna) would prefer to pursue Brexit in such a way that safeguards our economic prosperity and reflects the clear, but close, nature of the referendum result.

But there is one area where this veneer of temperateness collapses, where the whole carapace of equanimity is torn asunder. Pizza.

In short, Oliver thinks that pineapple is an acceptable topping for a pizza. He then compounds this transgression of good taste by holding that mushrooms — the mainstay of thousands of pizze ai funghi enjoyed every day throughout Italy — are only enjoyed by “savages”.

I suggest that this sort of rhetoric, which seeks to set down rigid rules about what is, and is not, a permissible topping for a pizza, is not so very far from the nonsense ramblings of the Brextremists, who claim (for example) that a future inside EFTA is ‘not Brexit’, or that Brexit ‘must’ mean something other than simply leaving the EU.

Of course, Oliver is just as entitled to his opinion as are the Brextremist cretins. I do not wish to silence John Redwood or Marcus Fysh, but that does not mean they should be able to spout their nonsense without being challenged. So this is my attempt to challenge the Norgrove position on pizza.

Not all Pizza is Pizza

In one sense, Norgrove is correct. There is no reason why, if the person consuming it finds it pleasant, pineapple should not find its way onto a pizza. Though he ought to recognise that it is illogical to take a laissez-faire view of pineapple and yet a prescriptive approach to mushrooms. In this he falls into a commonly observed trap, where it is often those who hold liberal views (in this case concerning fruit on pizza) who tend to be deeply illiberal once one scratches the surface (condemning mushrooms).

But I want to argue that not all pizza is pizza in the same sense. Just because a disc of bread is topped with tomatoes and cheese, that does not make it a pizza (is Socca, or Coca, pizza, for example?). Purists might even argue that (true) pizza is only to be found in Italy, or even just in Florence, Rome and Naples. Others might argue that pizza must be made by Italians, or Italian-trained chefs. I would argue neither, but I do think there is a case to be made for talking meaningfully about ‘traditional’ or ‘authentic’ pizza (and this means, of course, that we would have to distinguish between Neapolitan and Roman pizza).

Pineapple does not belong on traditional/authentic pizza (its absence from the best Italian pizzerias tells us that), but it does not follow that it does not have a place on what one might call ‘American Style’ pizzas, which are those we find in most UK takeaways and even chain pizzerias like Pizza Hut (though not Pizza Express).

Let’s think for a moment about a custard tart. It is a shortcrust pastry tart-case filled with a custard made from eggs and milk (or cream), sweetened and flavoured with nutmeg or vanilla. If you leave out the sugar and mix in ham and cheese, you have a dish which is not so very different, but which we’d call a quiche rather than a tart. The main features are still pastry and egg-custard, however.

Think about the dishes you enjoy at your local ‘Indian’ restaurant (ignoring the fact that your local ‘Indian’ is far more likely to be Bangladeshi or Pakistani than Indian). You might have Chicken Tikka Masala — a dish that you will never find on the streets of Lahore. If you order ‘Saag-Aloo’ it will probably contain spinach and potatoes, rather than the mustard greens found in the Punjab or West Bengal. And if you visit India and fancy Kedgeree for your breakfast, then it will contain no smoked haddock, just rather bland lentils. The waiter will probably assume that you are ill, as this is invalids’ food. This is all simply the way that cultural appropriation (rather than borrowing) works.

Cultural appropriation is a very good thing, of course. It is one of the phenomena that makes international trade possible and, as such, leads to prosperity. If we decided tomorrow that eating bananas was a vile form of colonial appropriation then it would be the poor farmers of India, Ecuador, Brazil, Central America, and the Caribbean who would suffer most. At least they could find consolation in knowing, as they sunk into poverty, that their main crop was once again pure from the hated imperial taint.

Pizza itself is the fruit of cultural appropriation and trade, over millennia. Before the arrival of tomatoes from the New World, it was just Focaccia, and it probably had its origin, like much European food, in the Middle East, perhaps Judea. Much of the pizza consumed in the UK (at least from take aways) has been ‘appropriated’ twice. First from Italy to America, and then from America to the UK. As with the dishes of the subcontinent that we call ‘curries’ (sic), we have modified pizza to conform to our own tastes.

American pizza is generally saltier and spicier and with a thicker base than one would find in Italy. The tomato sauce is more piquant (thanks to Mexican influences on US cuisine) and the cheese is sharper than the delicate, creamy Mozzarella or Burata used in Italy. One finds spiced sausage like pepperoni (an American invention) and even Jalapeños on some versions. The traditional Italian toppings, like pumpkin and aubergine, would be overwhelmed by the spicy tomato sauce. This means, of course, that while an Italian pizza would be dominated by a sickly sweet ingredient like pineapple, an American pizza can cope quite well. In fact, the sweetness of pineapple can even enhance an American pizza by cutting through the other elements of the salty, spicy, meaty topping. (I do not understand how any meat-free pizza could be enhanced by pineapple, however). And although pineapple would swamp a delicate cheese like Mozzarella, a harder cheese like Monterey Jack or Cheddar can hold its own.

Moreover, while Italian pizzas (in Rome, anyway) are made atop a thin, crisp crust, American pizzas have a heavier base with a scone-like texture. Pineapple has a high water content which would saturate a crisp base making it faccid, whereas the leaden base of an American pizza will remain defiantly stodgy, come what may.

At the end of the day, I believe in freedom. Unless you are Jewish or a Muslim, food is not a matter of religion, so you ought to be able to eat what you like. Even Pop Tarts. So I agree with Norgrove that when it comes to (American) pizza, pineapple is a perfectly licit topping, but only because American Pizza is pizza only by analogy. To proscribe mushrooms, however, is irrational and dangerously close to fascism.

Liberal pizzaiolos everywhere would, I am sure, agree.