We adapted Thomas Keller’s French onion soup recipe, no special belly-shaped bowls required
I have adored French onion soup my entire life — the gooey cheese, the spongy stock-soaked bread, the hearty beefy onions. If it’s on the menu, I’m ordering it. I’ve sampled hundreds of versions, from low-brow Wisconsin supper clubs where it’s almost all cheese, to unctuous veal broth versions in the all-night brasseries of Paris. The best I’ve ever had was at Thomas Keller’s Bouchon Bistros — both the Yountville and Las Vegas locations. I loved this soup so much, I bought the Bouchon cookbook so I could make it at home. But I’ve made it only twice, the first time because I didn’t know any better and the second because I had forgotten what a pain in the ass the recipe is.
To start, Keller has you slice eight pounds of onions. You then set a diffuser (you have one, right?) on the stove and cook the onions in a large pot. He doesn’t say how large the pot should be, though I’m guessing his is lots bigger than mine, as 28 cups of onion slices filled my 8-quart almost to the brim. You’re then supposed to cook the onions over very low heat for four hours, stirring every 15 minutes until they are caramelized. You must cook the onions slowly, Keller advises, because without such dedication you are certain to burn them. You also must enjoy this labor, Keller says in the headnote, because then your soup will be better.
If you say so, chef, but… my onions never browned. So much steam built up in the high-sided pot that the onions sweat down to a pile of slimy goo without a hint of color, even after four hours. I spent another 30 minutes cooking the goo over medium-high heat to finally achieve some color, but they still didn’t look like the blurry picture in the book. I wound up with four cups of caramelized onions, which was fine except then (and only then) did Keller mention that you’ll only need 1 ½ cups for the soup. Which would have been nice to know before I chopped 28 cups of onions.
Next, the chef instructs you to transfer the onions to another pot and add beef stock. The recipe doesn’t say how much beef stock, but instead directs you to page 319 for the sub recipe. To make the stock, you roast five pounds of 1- to 2-inch pieces of bone in a very hot (475-degree) oven for 45 minutes. (The high-heat roasting made my home smell like an abattoir and the aroma lingered for days, much to the chagrin of my vegetarian husband.) You’ll also need to roast some vegetables on a separate pan at a different oven temp and char half an onion in a dry saute pan over medium-high heat for 30 minutes. My pan bears the ghostly shadow of a burnt onion to this day.
All this fun goes into another soup pot with 20 cups of water to be simmered and skimmed for five hours. Then you ladle the broth gently from the pot through a fine mesh sieve. It should never be poured, Keller warns, because that would jostle the bones and lead to a cloudy stock, though once the soup is mixed with onions and covered in cheese, I’m not sure the clarity is so important. Oh, and you’ll need to strain the broth through cheesecloth too, because, well, I don’t know. I ended up with six cups of broth, though the recipe claimed I’d have 14, so I added some water to get the right amount. Whether or not you get the right amount of broth, you then must marry it with the onions in another pot with a fiddly herb sachet (more cheesecloth!) and simmer it for another hour.
This would be a good time to mention the serving vessels. Keller includes a scolding paragraph informing you that you can’t serve this soup in just any bowl, it must be the traditional belly-shaped French onion soup bowl. Without it, your ratios will be off, and the soup will not be perfect. Once you’ve distributed the soup among the correct bowls, you top each serving with toasted baguette slices and ⅛-inch-thick slices of Comté or Emmentaler that are also four square inches each. Slicing cheese off a small (costly) wedge of cheese into portions with that much surface area is extremely difficult. Perhaps if I had a 4-pound wheel of Gruyere and a spiral slicer it’d be a breeze, but with a regular knife it’s straight up dangerous.
The resulting soup is beautifully rich, but in my experience the onions sort of dissolved into the soup and lacked texture. Speaking of texture, I found the baguette slices a bit too thick; it was tough to get a spoon through them to make bite-sized pieces.
All in all, the soup took over 12 hours and made my house reek for days.
I love and need French onion soup, but not that much, so I’ve made a few adjustments. First, let’s talk about caramelized onions. I’ve worked in several restaurants and if there’s one thing chefs pound into your head, it’s that time is money. Thus, I learned to caramelize onions quickly using a large, low-sided pan (the better to evaporate the onion juices) over a much higher heat. The trick is to start deglazing with wine when the onions begin to crackle, and you think the stuck-on stuff in the pan is going to burn. It takes 45 minutes and it’s not the kind of thing you can walk away from, but it also doesn’t tether you to the stove for four hours and it works.
As for the beef broth, if I’m feeling like a weekend warrior, I’ll make it using an electric pressure cooker (3 pounds broiled beef bones, carrots, onions, celery, and 8 cups water, high pressure 45 minutes, natural release). But when a French onion soup craving strikes, I want it now, so store-bought broth it is. While canned beef broths generally suck, the current bone broth craze means there’s plenty of ready-made collagen-rich beef broth brands out there, and they add the lip-smacking quality that makes French onion soup great. There are tons of fairly good boxed brands you could use. I have found a fresh, locally made bone broth that has the consistency of Jell-O when cold, which indicates a broth with lots of collagen. Try bone broths made in your area to find one you like. Be warned that some of them taste a little sour thanks to the vinegar used to help extract collagen from the bones, so taste around before you settle on one for soup.
Bone broths give my French onion soup a lot of body, but they don’t always deliver enough meaty flavor, so I stir in a little Better Than Bouillon beef base to round out the flavor. Erase the idea of salt bomb bouillon cubes from your mind: Better Than Bouillon’s beef base is a refrigerated paste that actually has a fair amount of actual beef in it. Just a tablespoon or two ramps up the umami in my soup to 11. It’s cheating and would make Thomas Keller very angry, but I don’t have a Michelin star and this stuff works.
As for serving, I did not rush out to buy fancy-footed pot belly bowls with little lion heads on the side just because Thomas Keller told me to. My smallish, oven-safe bowls (about 4 ½ inches across) do a fine job of keeping my (slightly thinner) baguette toasts afloat while still holding up the cheese. Speaking of cheese, I use pre-sliced Gruyere or Swiss and then top it off with grated cave-aged Gruyere for the nutty funk I’ve come to associate with French onion soup. A quick pass under the broiler, and I’ve got a nice bowl of soup full of caramelized onions, a savory broth with lots of meaty overtones, and a crusty browned cheese cap with gooey pull and a toasty, garlicky baguette layer underneath. My French onion soup is no Michelin-starred dining event, but then again, French onion soup is a dish born of humble origins, so I’m okay with it.
French Onion Soup Recipe
Adapted from Bouchon
Serves 4 to 6
Ingredients:
4 large yellow onions (3 pounds)
3 tablespoons olive oil, divided
¾ teaspoon salt (plus more for seasoning)
1 cup dry sherry, dry vermouth, or dry white wine
2 teaspoons all-purpose flour
6 cups beef bone broth (one that isn’t too vinegary is best)
3 (3-inch) fresh thyme sprigs
1 bay leaf
1-2 tablespoons Better Than Bouillon Beef Base
1 garlic clove (peeled and left whole)
½ French baguette (7 ounces)
Freshly ground pepper
8 thin slices Gruyere or Swiss cheese
1 cup grated aged Gruyere or Comté cheese (about 5 ounces)
Instructions:
Step 1: Cut the top and root end from the onions and discard or save for stock. Cut the onions in half from the top through to the root end. Place the onions cut side-down on a cutting board and cut lengthwise (from the top to the root end) into ¼-inch slices. Break the onions up with your fingers, trimming away any root that prevents the onions from separating into pieces.
Step 2: Heat 1 ½ tablespoons of oil in a large cast-iron Dutch oven or large (12-inch) saute pan over medium high heat. Add half of the onions and the salt to the pan and cook, stirring frequently, until they have wilted a bit, 4 minutes. Add the remaining onions and reduce the heat to medium. Cook, stirring occasionally with a rubber spatula and scraping up the bottom and sides of the pan so stray bits don’t burn, until the onions are softened and the sticky bits you’re scraping up start turning a coppery brown, about 15 minutes.
Step 3: Start adding a generous splash of the sherry or wine to the pan occasionally to release any browned bits from the bottom and sides of the pan. Keep cooking, adding sherry now and then until the onions begin to make crackling noises and are the color of an old penny, 15 to 20 minutes. Adjust the heat as needed to prevent the onions from burning. Increase the heat if the onions are too pale after 15 minutes; stoves vary in power and a lot depends on the pan you are using. Stir in the flour and cook for 1 minute. Deglaze the pan with ½ cup of water and remove from heat.
Step 4: Scrape the onion mixture into a soup pot or Dutch oven with at least 3-quart capacity. Add the bone broth, thyme sprigs, and bay leaf and bring to a simmer over high heat. Taste the soup and add the bouillon base 1 tablespoon at a time, stirring to dissolve and tasting between additions, until the soup is super delicious. Cover, reduce heat to medium-low, and cook for 30 minutes to meld the flavors.
Step 5: While the soup simmers, prepare the baguette toasts. Preheat the oven to 500 degrees. Line a small, sturdy rimmed baking sheet with foil (the lower half of a broiler pan is ideal). Rub the garlic clove all over the outside of the baguette to season it subtly with garlic. Cut the baguette into ⅓-inch slices on an angle (to produce slices with more surface area). Arrange the slices in a single layer on the baking sheet and brush with the remaining 1 ½ tablespoons of olive oil and season with salt and pepper. Bake until the edges of the bread are crisped but not totally brittle, about 4 minutes. Set the toasts aside and keep the baking sheet as it is.
Step 6: Preheat the broiler and adjust the oven rack so it is 6 inches below the broiling element (usually the second-highest setting). Place 4 oven-proof soup bowls on the foil-lined baking sheet, leaving about 3 inches between them. Ladle the soup into the bowls leaving ½ inch of headspace at the top; discard the bay leaf and thyme sprigs. Float 2 toasts on the top of each bowl of soup (you may not need all the toasts; if not, serve the extras at the table for dunking). Carefully drape 2 slices of cheese over each bowl, making sure they hang over the sides a bit. Gently sprinkle the grated cheese evenly over the top of the sliced cheese and to fill in any gaps of bread or soup that remain uncovered with cheese.
Step 7: Carefully slide the baking sheet into the oven and broil until the cheese is browned in places and bubbly, 5 to 7 minutes. Watch carefully so the cheese doesn’t burn and rotate the baking sheet as necessary so that the cheese browns evenly. Very carefully transfer the soup bowls to dinner plates and serve.
Ivy Manning is a Portland, Oregon-based award-winning food writer and author of 10 cookbooks, including Tacos A to Z: A Delicious Guide to Nontraditional Tacos. She is a regular recipe tester and editor for Eater as well as for restaurants and appliance brands.
Dina Ávila is a photographer living in Portland, Oregon.
