6 tbsp. salted butter, cut into 5 to 6 pieces
30 leaves fresh sage
4 large shallots, very finely chopped, about 2 cups
4 cloves garlic, finely chopped
Salt and black pepper
⅛ tsp. freshly grated nutmeg
1 cup beef bone broth or stock or mushroom stock
1 lb. farro spaghetti (I like Rustichella d’Abruzzo)
½ cup freshly grated Parmigiano-Reggiano, plus more for passing
Bring a large pot of water to a boil for the pasta.
Heat a large skillet over medium. Add the butter. When it foams, add the sage; cook, stirring often, until the leaves curl at the edges and the butter is brown, 3 to 4 minutes. Transfer the sage to a plate lined with paper towels. Add the shallots and garlic to the brown butter. Season with salt and pepper and add the nutmeg. Reduce heat to medium-low; cook, stirring often, until the shallots are soft, 6 to 7 minutes. Add the broth, increase heat to medium, and bring to a simmer. Reduce heat to low.
Meanwhile, salt the boiling water, add the pasta, and cook 1 minute less than package directions. Reserve about 1/2 cup of the cooking water, then drain the pasta.
Add the pasta to the skillet and sprinkle in 1/2 cup cheese. Crumble half of the sage leaves over the pasta. Toss, using the reserved cooking water as needed to create a creamy sauce that clings to the pasta. Divide the pasta among shallow bowls; top with the remaining sage. Serve with more cheese for passing at the table.