Easy French Onion Soup Recipe

French onion soup isn't typically one of those recipes that people label "easy." But as recipe developer Nathaniel Lee of Beginner Food points out, this easy French onion soup recipe requires only six ingredients, needs no special equipment, and allows for a "wide margin of error...in terms of salting and reduction" due to long periods of time between steps. So, if you're trying to decide on a new appetizer or side dish to serve with a dry roasted meat, like a steak or roasted chicken, it's worth adding this recipe to the menu.

While making this easy soup, just be conscious of steps that need to be performed in parallel, and stay mindful of time. "The first parallel step is slicing your bread and grating your cheese while your onions sauté," says Lee, adding that "the next parallel step is toasting your bread while finishing the soup." But he offers a quick tip to make sure you get the second parallel step right. Given that the soup takes an hour to cook, simply set a time to go off at the 50-minute mark to remind you to get your bread in the oven to toast. Easy enough? Then let's get started!

The beauty of this classic French onion soup recipe is that it requires so few ingredients with very little prep work. Simply gather a stick of butter, four onions (any version will do), half a bottle of red wine, two cartons of beef stock, a half-loaf of country bread from your local bakery, a cup of shredded Gruyere cheese, and several tablespoons of salt. The thing is, with so few ingredients, each ingredient really is important to the overall taste of the dish. Specifically, while you can use any red wine, there are reasons why a pinot noir or burgundy are best. "Traditionally, French onion soup is made with burgundy wines which are medium body, dry, and have slight spice," Lee explains. "Any red wine can be substituted in a pinch, but whatever wine you use will impart significant flavor to the dish. I would not recommend very heavy or sweet wines like zinfandel, merlot, or syrah, unless those taste profiles are specifically desired."

French onion soup, of course, features a heavy dose of onions. So, go head and start your prep work by peeling and slicing your onions thinly. They don't have to be completely uniform in shape or size, but be sure to slice each onion in half before slicing them thinly, so that you're working with crescents of onions rather than full circles. When your onions are sliced, place your butter in a skillet and heat to medium-high, until the butter browns. Add the onions to the pot and saute for 15 minutes, until they're lightly browned and softened.

As the onions are sautéing, use your time to prep your bread and cheese. Slice the bread into ½-inch thick slices and set aside, then grate your cheese. Of course, if you can find a pre-shredded Gruyere cheese, there's no need to take the time to grate your own, but Lee points out that's typically tricky. "Finding pre-shredded Gruyere is fairly difficult," he explains. "It's normally sold in a block unless you have a very well-stocked grocery store." Lee also notes that you could switch out the type of cheese and veer away from Gruyere altogether. "If you're using a different melting cheese like jack or provolone, shredding it yourself allows you to pick cheeses with specific water content," he notes. "The less moisture of fat or water in the cheese, the less stringy it will be." It's all about personal preference!

With your bread and cheese prepped, head back to the stove and start turning those onions into soup. Go ahead and add the wine and beef stock to the pot. You'll allow the soup to cook on high for a full hour. Just remember, set your timer for 50 minutes rather than 60 minutes as a reminder to toast your bread before the soup has finished cooking. Also, now's the time to go ahead and preheat the oven to 425 F so that it'll be nice and hot for toasting your bread. 

When the alarm you set goes off, it's time to get the bread in the oven. Place the slices of bread on a cookie sheet and distribute the shredded cheese evenly between the pieces. Pop the bread into your pre-heated oven and turn on the oven light so it's easy to see the bread's progress. Allow it to toast for roughly eight minutes (it's helpful to set another timer) — you want the cheese to be melted and the edges of the bread to look golden brown. 

After you've pulled your toasted bread from the oven, your soup is almost ready to go. You may have noticed you still haven't used the several tablespoons of salt you have set aside. Now's the time to add the salt, little by little, to taste. "I recommend salting at the very end so the cook does not need to anticipate the effects of reduction in concentrating the salt flavor," Lee says. When you're satisfied with the flavor, it's ready to serve! Simply top each bowl of soup (the recipe makes four to six servings) with a slice of the cheesy bread. And just like that, you've got a warm, hearty bowl of French onion soup.