In a large pot, bring water to a boil.
Stir in the salt and pasta, then reduce heat to medium and cook, stirring occasionally, until pasta is almost al dente, starting to become tender, but not yet soft, about 5 minutes.
Stir in the milk and sugar, then continue to cook just until pasta is tender and the milk is starting to thicken, stirring the bottom and sides often to prevent sticking.
Season to taste with additional sugar and salt, if desired.
Divide among serving bowls and, if desired, top with a small piece of butter and pinch of cinnamon sugar. Serve immediately.