Peel and cut the pear in small cubes then quickly fry them in a little bit of olive oil just until they start to brown, add a pinch of salt then set aside.
In the same pan drizzle a little bit more of olive oil and toast the rice at medium heat for a minute, then add the finely chopped onion and cook another 1 minute.
Pour the white wine and let it evaporate completely, then add a couple of ladles of stock and bring the heat to low; add more stock as soon as the rice absorbs it.
Stir every once in a while to make sure the rice doesn't stick to the pan and cook until the rice is "al dente", soft but with a bite.
When the risotto is nearly ready (at this point there should be almost no liquid), add the Gorgonzola cheese and let it melt; then add the pears with the butter and the Parmigiano cheese and turn off the heat.
Mix well so the risotto will become smooth and creamy then add some freshly ground black pepper on top. Serve immediately.