The Associazione Verace Pizza Napoletena (VPN), a nonprofit organization established three decades ago to “promote and protect true Neapolitan pizza” has accredited 76 restaurants across the US, according to the report on Thursday.

One pizza-maker from Phoenix, Justin Piazza, was quoted as saying that he invested $25,000 (€18,100) in buying special equipment to make ‘true’ pizza, including a wood-burning oven which features bricks made from the ashes of Mount Vesuvius, the volcano that wiped out Pompeii in 79 AD.

The certification also requires using certain ingredients in line with the association’s regulations as well as spending six months learning the art of pizza-making, “including handling the dough with a deftness that VPN boosters say approaches a kind of artistry”.

But perfecting the Neopolitan doesn’t come cheap: on top of spending huge amounts on equipment and classes, which take place at a school in the Los Angeles area, the VPN also charges a $2,000 (€1,488) application fee, leaving some pizza-makers pessimistic about its value.

"A pizzeria should be judged on how its pizza tastes, not on what alphabet soup is on its sign, or on whether the toilet paper in its bathroom is imported from Naples,” Adam Kuban, founder of Slice, a blog that is part of the Serious Eats site, wrote in 2011.

The Wall Street Journal reported that although Kuban stands by those comments, he admits that the VPN stamp “establishes a default quality of pizza”.

Competition is fierce among pizza-makers around the world to perfect the Naples speciality. In April, an Australian man scooped the prize for the best Neopolitan at a competition in Parma.

READ MORE HERE: Australian makes the world's best Neapolitan

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