Here’s a recipe from Osteria Morini, a restaurant in New York City focusing on the cuisine of Emilia-Romagna, a region known for its prosciutto and its Parmigiano-Reggiano cheese, both featured prominently in this recipe.
In a pot, bring the chicken stock to a boil over high heat.
Put all but 2 tablespoons of the cheese in a large, deep, heat-resistant bowl. Pour ½ a cup of the boiling chicken stock over the cheese. Using an immersion blender, blend on high speed until the cheese begins to melt. (If you don’t have an immersion blender, you can transfer the mixture to a regular blender and process at high speed.)
With the blender running, add the olive oil and truffle oil (if using) and continue blending until the sauce is smooth and emulsified. Transfer the sauce into a small pan, cover, and keep warm over very low heat.
In a large skillet, melt the butter over medium-high heat. Add the onion and garlic and cook, stirring, until the onion is translucent, 1-2 minutes. Add the radicchio, prosciutto, the remaining chicken stock, and thyme. Return to a boil, then reduce heat to medium-low and simmer until heated through, 2-3 minutes. Season with salt and pepper, to taste. Keep warm.
Meanwhile, bring a large pot of salted water to a boil. Stir in the pasta and cook until al dente, about 2 minutes for fresh pasta, then drain. For dried pasta, follow the package directions. Drain the pasta in a colander, and reserve.
Remove the sauce from heat. Stir in the reserved 2 tablespoons of grated cheese. Add the pasta to the sauce and turn to coat evenly. Divide the pasta among 4 large plates. Sprinkle with additional cheese, ground black pepper, drizzle a little olive oil over the pasta, and serve at once.