For the Risotto:

In a saucepan, heat the chicken or vegetable broth and keep it warm over low heat.
In a large pan, heat the olive oil and 1 tablespoon of butter over medium heat. Add the chopped onion and sauté until soft and translucent, about 5 minutes.
Add the Arborio rice to the pan and toast for 2-3 minutes until slightly translucent.
Pour in the white wine and cook until mostly absorbed, stirring frequently.
Soak the saffron threads in 2 tablespoons of warm broth for a few minutes.
Gradually add the warm broth, one ladle at a time, stirring constantly until absorbed. After about 10 minutes, add the saffron mixture.
Continue adding broth and stirring until the rice is creamy and al dente, about 18-20 minutes total.
Remove from heat, stir in the remaining butter and Parmigiano-Reggiano cheese, and adjust seasoning with salt and pepper
Spoon the risotto onto plates or into bowls, garnish with fresh parsley or extra cheese if desired, and serve warm.