Bring salted water to a boil. Gently cook the pasta for 3–4 minutes, until they float and are tender.
Make the brown butter sage sauce:
While the pasta cooks, melt butter in a large skillet over medium heat.
Add sage leaves and cook until butter browns and smells nutty (about 3–4 minutes).
Season with salt and a splash of lemon juice or white wine, if desired.