8 cups chicken stock, heated (you may have stock left over)
4 tablespoons butter, cut into pieces
1/2 cup freshly grated Parmigiano-Reggiano, plus more for serving
Heat the olive oil in a wide, low saucepan over medium heat until hot. Add the onion and cook until translucent and softened, about 8 minutes. Make sure not to brown the onions. Add the rice and stir to coat each grain. Cook until they are opaque, about 4 minutes.
Add the white wine and cook for 3 minutes, or until the liquid has absorbed. Add 1/2 cup of simmering broth and stir until almost completely absorbed. Continue cooking the rice by adding the broth one ladle at a time, stirring often and allowing each addition of broth to be absorbed before adding the next.
Continue this process until the rice is tender and creamy, yet still firm to the bite (al dente), about 22 minutes total.
Remove from the heat. Stir in the grated Parmigiano and butter. This last touch of butter gives extra shine and creaminess to the dish. You may need an extra ladle of broth at this point to keep it loose and creamy.
Ladle into flat soup bowls. Serve with additional Parmigiano.