My neighbor brought this over when we first moved in and it blew my mind.

For a touch more flavor without adding extra ingredients, brown the beef very well, letting it get dark and crusty in spots before adding the broth; those browned bits are where the magic happens. If you like a little extra comfort, use a mix of cheddar and any other meltable cheese you have on hand, such as Colby or Monterey Jack, as long as the total amount stays the same. You can also swap the heavy cream for half-and-half in a pinch; the sauce will be slightly less thick, but still creamy—just simmer a minute longer before adding the cheese. If you prefer, use small shells or elbow macaroni instead of curly pasta; the important thing is a shape with nooks and crannies to catch the sauce. To stretch the dish for a crowd, stir in an extra handful of cooked pasta and thin the sauce with a bit more broth or pasta water. Leftovers reheat best over low heat on the stovetop with a splash of milk or cream to bring the sauce back to life. If you want to sneak in some vegetables without changing the five-ingredient base, you can serve steamed peas or broccoli on the side and let everyone stir them into their own bowl.