Try not to freak out when I say this: Authenticity is overrated. Case in point? The double-layer pizza at Via Mercanti in Toronto. It's a tasty concoction, despite my sincere doubt that there's any region in Italy specializing in two-layer pizzas (of course, now that I've made that proclamation, I'm sure the comments will light up with people telling me about Italy's centuries-old history with multi-layered pizzas).
You'll find the restaurant nestled among the Mexican grocers and hippie hangouts of Kensington market; it's a fairly unlikely spot for a low-key pizzeria such as this, but then good food fits in wherever you find it.
The double-layer pizza (dubbed the Via Mercanti, after the restaurant) is basically what would result from the union between a Margherita pizza and a calzone. The top layer is a pretty typical Margherita pizza, and the bottom consists of ricotta cheese, diced prosciutto cotto and hot soppressata, and mushrooms.
It sounds overstuffed—and it kind of is—but in this case, I suspect that's the point. This is not an elegant pizza. It is, as my dining companion called it, a cheesy, saucy mess.
The bottom layer of crust sogs up a bit under the heaving weight of all that sauce and cheese, though it does retain a modicum of exterior crispiness and a good amount of chew. The second layer, on the other hand, is essentially lost amidst all the sauce, cheese, and toppings.
This means that the whole two-layer conceit is basically just a gimmick; the layers aren't clearly defined, and ultimately coalesce into one thing (if I tried this in a blind taste test, I don't know if I'd even be able to tell that there's more than one layer).
All that said, it's pretty darn tasty. The no-frills sauce, the cheese, and the sausage and mushrooms all work quite well together. It's not the best pizza I've ever had, but I'd happily eat it again.
Make sure you drizzle it with their house-made chili oil, which is redolent of the distinctively sweet flavor of roasted red pepper.