This is from a reply to a comment on the blog post, asking about using raw pasta.
Leaving it here for my own future reference:
"If I’m cooking 1 cup raw pasta, I add about 1 1/2 cups water. Do this after you brown the meat and before you add the cheese. One good recommendation I can make is trying the special pastas especially made for one-pot cooking. Barilla was the first to come out with this–I forget what they call it–but it does work wonderfully."