1/2 head radicchio (I used Treviso Radicchio), cut crosswise into 1/2 inch wide ribbons
4 tablespoons unsalted butter
1/4 cup freshly grated parmigiano reggiano
1/2 cup freshly grated grana padano
In a medium sauté pan, heat the olive oil over medium heat. Add the onion and cook until soft and translucent, around 5-7 minutes. Add the rice and stir with a wood spoon until toasted and opaque, around 3 minutes.
Add the wine and a ladleful of chicken stock. Stir and cook until the liquid is absorbed. Add another ladle or two of stock and bring to a boil. Add the radicchio and stir, cooking and stirring until the liquid is absorbed. Continue stirring and adding stock one ladleful at a time, letting is get absorbed and then repeating, until the rice is creamy and tender but still a bit al dente, about 18-20 minutes.
Remove the pan from the heat, add the butter, parmigiano reggiano, grana padano and stir to combine. Taste. Season with sea salt and black pepper if necessary. Divide the risotto among individual plates or low bowls. Drizzle with olive oil and finish with freshly grated parmigiano reggiano cheese and some black pepper.