My hubby rated this dish 6 stars out of 5!

Variations & Tips
For a different twist, try using Gruyère cheese instead of Swiss for a nuttier flavor. You can also add sliced mushrooms to the onion mixture for an earthy depth. If you prefer a bit of heat, a pinch of red pepper flakes can be added along with the garlic. For a lighter version, substitute ground turkey for the beef and use whole wheat pasta.