2 tablespoons of extra-virgin olive oil (EVOO), plus some for drizzling
2 large onions, thinly sliced
Salt and freshly ground black pepper
1 pizza dough, from your favorite pizza shop or store-bought
1/4 pound sliced prosciutto, cut into strips
1 cup grated fontina cheese
1/4 pound gorgonzola cheese, crumbled into small pieces
Preheat oven to 425F.
Preheat a large skillet over medium-high heat with the butter and 2 turns of the pan of EVOO, about 2 tablespoons. Add the sliced onions, season with salt and pepper, and cook; stirring frequently for 20-25 minutes or until very brown and caramelized. Remove from skillet and let cool slightly.
Drizzle a little EVOO on to the pizza dough and pull and stretch until almost the same size as the baking sheet pan. Drizzle the baking sheet pan with EVOO, then set crust in place. Poke the pizza dough in several areas with the tines of a fork. Season the dough with salt and pepper, and spread the caramelized onions on top. Top the onions with the prosciutto, then the fontina and gorgonzola cheese.
Transfer to the oven and bake until the dough is cooked through and the cheese melts, about 20 minutes. Remove, cut into portions and serve.