Ludo Lefebvre's Secret Ingredient For Perfect French Onion Soup

French chef Ludo Lefebvre brought hearty French cuisine to the Los Angeles food scene, melding tradition with innovation in such a way that his food has become a staple in the vibrant City of Angels. Lefebvre spent 12 years learning French cooking from several renowned French chefs before moving to California, and he brought his highly prized set of culinary skills with him. Now, you can take home a few of his tips for cooking up French staples.

In 2019, the culinary star spoke with Food & Wine and shared a few key pointers for making the perfect bowl of French onion soup. Some of Lefebvre's tips for the classic dish are relatively straightforward, like his suggestion to use a neutral oil with a high smoke point to caramelize your onions (he uses grape seed oil), but there's one small addition that might be the key to taking your next bowl from blah to unbelievable.

The best part about Lefebvre's secret ingredient? You probably already have it in your fridge. It's Worcestershire, that tangy, dark brown sauce that's often tossed into Bloody Mary recipes or used as a marinade for meat-based dishes. Lefebvre was concise when he explained the unconventional addition to his recipe, noting, "It really brings back more flavors of the beef." This is undoubtably true, given that the sauce is often paired with steaks and beef-based foods. This is what makes it perfect for French onion soup, as it highlights the dish's oft-forgotten beefy base.

Worcestershire sauce's ability to enhance savory, meaty meals is unmatched. It's a certified umami booster, bringing a depth of flavor not just to Ludo Lefebvre's signature French onion soup, but to a number of dishes (and even drinks). But what makes Worcestershire sauce so amazing, and what is it, exactly? Most home cooks have a bottle stored in their fridge somewhere, but few people know precisely what's in the dark brown, savory sauce. Most Worcestershire sauces have a vinegar base and contain molasses, anchovies, onion, anchovies, tamarind, and garlic. Different brands do switch up some ingredients to add their own personal touch, but those listed above are the key to the sauce's particular, intriguing taste.

Complexity is key to Worcestershire's flavor-enhancing power, as the anchovies' umami brings out the meaty flavors of whatever it's added to. The molasses adds a rich sweetness, and the aromatic aspects of onion and garlic are sure to enhance any dish. Incidentally, all of these flavors work particularly well for French onion soup. Molasses enhances the caramelized onion, and the anchovies bring out the beef taste of the broth. This, in addition to the tangy taste of vinegar, makes it the perfect "secret ingredient" for this French classic.

Now that you know why Worcestershire sauce is such an excellent flavor enhancer, you might be wondering what other French onion soup tricks Ludo Lefebvre has up his sleeve. According to his Food & Wine interview, he has a few major pointers for those hoping to up their soup game, even beyond the flavor enhancement of Worcestershire sauce.

For starters, Lefebvre recommends very particular handling of your onions. He suggests removing the core of each, as "It's a little bitter." Another key is to separate your onion layers after slicing them; this will help them cook more evenly. As for which onion variety you should choose (after all, there is a difference between white and yellow onions), Lefebvre highlights yellow onions both for their texture and their ability to caramelize with ease.

When you're cutting your onions, Lefebvre implores that you be cautious with your knife. Though you may be tempted to cut your onions into the thinnest slices possible, you should cut them into thicker slices so that they maintain their texture when caramelizing. These tips, combined with Lefebvre's genius addition of Worcestershire sauce, are sure to help you make one incredibly tasty batch of the iconic — and, of course, quintessentially French — French onion soup.