The Unique Ingredient That Adds Rich Flavor To French Onion Soup

If you're itching to make French onion soup, chances are you're looking for a rich dish. On its own, this soup delivers in this arena, as most recipes are chock-full of butter, red wine, beef stock, and cheese. And yet, if it's chilly outside and you're looking for a way to make your meal extra-cozy and satisfying, try incorporating a little duck fat.

In the beginning of French onion soup recipes, you're usually sauteing plenty of onion slices at medium-high heat — so you'll want a fat that can hold up at this temperature, which duck fat is perfect for. But beyond the logistics, this ingredient contains plenty of delicious umami flavor (which is why we also love using it to fry latkes) that will add a complex, meaty taste to your onions (and ultimately your soup). It also has a touch of sweetness, which will build on the caramelization of your veggies, and a wonderfully creamy consistency. And, as a bonus, the majority of duck fat is made up of unsaturated fatty acids, like olive oil and other ingredients we consider "good fats."

As tasty as duck fat is, most of us don't have it sitting around in our cupboard. If you happen to be cooking duck before you make your soup, you can render the fat by making little pricks in your poultry so the juices can seep out, then straining and saving them. However, you can also buy jars of duck fat online. Fatworks offers an excellent option, made from cage-free ducks and flavored with organic rosemary extract. Epic Provisions sells a slightly more affordable choice, which comes from ducks that aren't kept in individual cages.

When it's time to cook, you have a few options for how to use your new product. As we mentioned, you'll deploy it as the first step of your recipe, right before you throw in the sliced onions. You'll want to use between two and four tablespoons per 64 ounces of broth, and you'll first want to melt it in your pan. However, you can also go half and half with butter and duck fat, or use a little of each of those with some olive oil. If you'd like to build on the rich flavor of this bird even more, however, you can also incorporate it into the stock. Either go half and half with beef or duck stock or just dunk the latter in your pot for the richest flavor possible.