We had a chilly weekend in San Francisco. It was foggy and overcast – perfect weather for soup! We decided to go with something simple and easy. French onion soup is surprisingly easy to make, only has a few ingredients, and makes great lunch leftovers for later in the week.
French onion soup takes a lot of onions (at least 10 or 12). We’ve found that a Japanese mandoline is by far the fastest and easiest way to tackle the prep. It keeps the slices consistent, and allows you to work quickly in case your onions are extra pungent and make you cry. We’ve tried several different ones, but this one is our favorite mandolin. We’ve noticed when we wear contacts or put the onions in the refrigerator before cutting, it helps with the crying. We didn’t do either this time – whoops!. Do you have any secrets?
You’ll end up with quite the pile of onions. This was just one bowl of a few we filled. We like to make this on the weekend because it takes a long time for the onions to cook. We prep extra individual servings and pop them into the oven for a weeknight dinner on a quarter pan sheet tray (easiest weeknight dinner ever, and practically no clean up).
Be careful when the soup comes out of the oven, because it’s always super hot, probably from the heat trapped under the topping of the bread and cheese. Make sure that you put a piece of bread that covers the majority of the surface of the soup. Don’t settle for a crouton or small piece of toast! For this one you’ll want to go big or go home. Lots of cheese and bread. Remember, you’re basically eating vegetables and broth right? So load it up!
If you’ve never made this at home, you need to try it. It’s so much better than the kind you can get at fast-casual restaurants, and you definitely don’t need a bread bowl. Make sure to use good Emmental, Comte, or Gruyere cheese!
- Cut the top and bottom off each onion and slice through vertically. Using a Japanese mandoline, shave each onion half into very thin slices (approx. 1/16").
- Melt the butter in a large dutch oven or stock pot. Add all of the onions and cook uncovered over very low heat, stirring every 10-15 minutes. It will seem like nothing is happening for about the first hour. This is normal. It's important to cook them gently.
- When you start to see liquid accumulating in the pan from the onions, turn up the heat slightly. Continue cooking very slowly until the liquid is evaporated and the onions begin to color. Once they begin to color, the process moves much more quickly, so stir frequently.
- Continue cooking the onions until they are very dark and caramelized, then sprinkle with flour and stir in. Add the beef broth (if you want more volume of soup, you can add an extra quart, it will just have more broth).
- Put the bay leaf, peppercorns, and 3-4 thyme sprigsin a sachet and simmer in the soup for 30-40 minutes. We use these pre-made cheesecloth sachets. They are really convenient.
- Once the soup has simmered 30-40 minutes, salt to taste and ladle the soup into individual porcelain or ceramic serving dishes (oven safe!).
- Top each bowl with a slice of bread that covers most of the top surface of the soup. Grate a generous amount of cheese over the top of each dish, then put under the broiler in the oven until the cheese is golden and bubbly. Watch it carefully to make sure it does not burn!