Prepare the caramelized red onions and preheat your oven to the highest possible heat.
Form the pizza dough into a ball. Start by making a circular motion with the palm of your hand, applying some pressure. Then release the pressure gradually until you get a nice ball shape. Put your pizza dough ball on a lightly floured work surface. Dust it with a little more flour, and let it proof, covered with a kitchen towel, for another 15 minutes.
Shape your dough into a large, thin disk and place it in a pizza pan.
Put the tomato purée (passata) on top of your pizza dough, in the middle. With the back of a spoon or a ladle, using circular motions toward the edges, make sure the tomato covers your pizza dough. Leave an edge about 1 inch (2-3 cm) thick.
Drizzle a few drops of extra virgin olive oil and sprinkle with dried oregano and salt.
Add your mozzarella cheese. Just tear it into bite-size pieces and place them over the tomato sauce.
Crumble the Gorgonzola on top of your pizza in pieces about 1 teaspoon in size.
Heap the caramelized red onions on top of the other toppings.
Transfer your Gorgonzola pizza to the oven. Bake for 10 minutes, or until the edges are slightly browned.