Cook the spaghetti in a large saucepan of boiling salted water until al dente. Drain and keep warm
Heat the oil and butter in a frying pan and cook the garlic and sage leaves for 1 minute. Stir in the bread crumbs and cook until golden. Season to taste with salt and ground black pepper.
Add the bread crumbs to the spaghetti with the Parmesan cheese and toss to combine. Serve at once in warmed pasta bowls.