In a large, heavy-bottomed pot or skillet, heat the olive oil and butter over medium heat. Add the onion and salt and sauté until it becomes translucent, about 5 minutes.
Add the Arborio rice to the pot and stir to coat the grains with the oil and butter. Cook for about 2-3 minutes, until the rice is slightly toasted and translucent around the edges.
Pour in the saffron-infused white wine and stir continuously until it is mostly absorbed by the rice, about 2 minutes.
Once the wine is absorbed, begin adding the warm broth to the rice, one ladleful at a time, stirring frequently. Allow the rice to absorb most of the liquid before adding the next ladleful. Continue this process for about 18-20 minutes, or until the rice is creamy and al dente.
Once the rice is al dente, remove the pot from heat. Stir in the grated Parmesan cheese until well combined. Season with salt and black pepper to taste.
Serve the risotto hot, garnished with chopped fresh parsley if desired.