For the spaghetti with sage butter, cook the spaghetti al dente according to the package instructions. In the meantime, finely chop the sage, reserving 2 leaves for garnish.
In a small pan, melt the butter and briefly fry the chopped sage in it, adding a little salt. Arrange the cooked spaghetti on plates and spread the sage butter over it.
Garnish with the grated Parmesan cheese and the sage leaf.