The Key Ingredient: Onions
The humble onion does a magic trick as it cooks; initially sharp and strong, it develops into a silky, golden, sweet ingredient when patiently cooked over low heat. Low and slow-cooked onion adds complexity to so many dishes.

For this recipe, we’re not quite caramelizing (which involves taking them to a deep brown color), but still developing tons of flavor, particularly with the additions of thyme, bay leaves, and wine. Half of the flavorful onions are added to the meatballs, while the other half are added to the sauce.

The Best Beef for French Onion Meatballs
To ensure your French onion sauce doesn’t become too heavy or oily, be sure to buy lean ground beef for these meatballs. You’re adding cheese and butter at various points in the recipe, so there won’t be a lack of richness (and deliciousness!).

If you’re feeling adventurous, substitute the ground beef for ground lamb. Or try ground chicken for a lighter version of the dish—just be sure to use ground chicken that contains both white meat and dark meat to prevent the mixture from becoming dry.

The Finishing Touches