This recipe can be prepared in 45 minutes or less.
Fill a 4-quart kettle three fourths full with salted water and bring to a boil for macaroni. Cook macaroni in boiling water until al dente and drain in a colander.
While macaroni is cooking, in a non-stick skillet heat butter over moderate heat until foam subsides and add bread crumbs, sage, and salt and pepper to taste. Cook bread crumb mixture, stirring, until golden brown, about 3 minutes. In a large bowl stir together mascarpone and Parmesan. Add macaroni and salt and pepper to taste, tossing to combine.
Divide macaroni between 2 bowls and sprinkle with seasoned bread crumbs.