The huge black stones from which the walls are built around the old town in the heart of the chaotic city of Naples may well be volcanic. However, I wonder if their greasy and almost unattractive patina might possibly be down to the fact that they enclose the birthplace of the pizza, and that their glistening sheen might therefore the result of hundreds of years of oil and cheese hissing, spitting and bubbling away as pizzeria ovens carry out their daily work.
Yet a visit to the ancient city a couple of years ago was disappointing - on the gastronomic front, that is. The pizza has conquered the world, so one might assume that here, in the square mile of its conception, a definitive recipe may still exist.
Well, it does. Unfortunately.
Extensive research revealed a very limited number of variations. Trudge the stone-sett streets and peer into the tiny cave-like pizzerias tucked in to the base of those titanic stone colonnades and in the old town of Naples you will find only three kinds of pizza on offer. Cheese, tomato and (for those who feel like splashing out) cheese and tomato.
And that's it. Half a mile to the west, the glistening Mediterranean teems with anchovy, octopus and shellfish. The hills of Campania towering over Italy’s fourth richest city abound with cattle, poultry, fresh vegetables, olives, nuts and fruit, yet none of these make it across the A56 autostrada at Capodimonte and into the city to embellish what is a disappointingly frugal repast.
It has taken the rest of the world to acknowledge that Naples has only created a base (literally) to work from. Wonderful, imaginative and delicious variations crowd the menus of pizzerias around the world, yet Naples is bereft. In some puritanical way, the Neapolitan has eschewed the attempts of incomers to corrupt his staple meal and, as a result, since the dawning of the pizza age, nothing has been allowed to change. Even in 2004, a law was passed to ensure that the recipe for a true Neapolitan pizza remains constant: wheat, yeast (the law specifies which kinds) tomatoes, oil and salt. The cheese, if added, must be a locally sourced Mozzarella.
Of course, if anyone wanted to change what the Neapolitans started all those years ago, it is not just the weight of the Italian legal system that they would find coming down on them. The people of Naples can count on some pretty influential cronies to help them preserve their status quo...
So it is the rest of the world that has taken the pizza by the horns and dragged it into the 21st century.
In Rwanda's bustling capital city of Kigali, there is a very popular Italian restaurant which offers a comprehensive range of pizzas on its menu. Last week, my man there paid it a visit with a group of friends, and they all enjoyed a meal together. However, having glanced through an internationally familiar menu and ordered, he was a little put out when his pizza arrived. It was of distinctly vegetarian appearance, an attractive presentation of red, yellow and green peppers. But it wasn't what my man thought he had ordered. "Where's the sausage?" he wondered.
He called the waiter over and asked to see the menu. Sure enough, my man had made a simple oversight, and not even in reading the small print. Somewhere down the line into darkest Africa, the transliteration had gone askew. Yet the kitchen had obediently adhered to what was printed in the menu.
My man hadn’t ordered “Pepperoni” after all.
He'd ordered “Pepper only”.