Simmering the balsamic vinegar both mellows and thickens it. When tossed with the hot pasta and the butter, it forms a smooth, uniquely flavored sauce.
To make this dish the traditional Roman way, mix the cheese, eggs, pepper, and pork in a bowl to create a thick sauce before tossing it with the pasta.
What makes this chili best-ever is a toss-up. The salsa? The cheese? That creamy dollop of sour cream? The fact that it's low-cal and low-fat? Whatever. Best-ever.