Name: French Onion Soup
Prep time: 60 min
Cook time: 30 min
Total time: 90 min
Ingredients: 2 tablespoons butter; 2 tablespoons neutral oil; 8 small onions (sliced thin (or 5-7 medium onions)); ½ cup dark beer; 3 tablespoons minced garlic; ¼ teaspoon dried sage; ¼ teaspoon dried thyme; 4 cups vegetable or beef broth; 2 teaspoons salt (only if using unsalted broth or stock); 1 cup shredded cheese (Swiss or Gruyere); 6 slices of crusty bread

There are few meals we enjoy more thoroughly on a winter’s day than this French onion soup. Made with an abundantly herbed broth and caramelized onions, the true pièce de résistance is the topping of sourdough bread cubes and toasted cheese. Even if you’ve never tried French onion soup before, I highly recommend giving this recipe a try.

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Two bowls of french onion soup sit on a wooden surface. Each bowl of soup is topped with bread cubes and toasted cheese. A silver spoon sits on a blue napkin in the foreground.

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This French onion soup recipe is adapted from my mother-in-laws version, which originates in one of the most classic cookbooks of the 20th century: The Joy of Cooking. My in-laws have long appreciated this cookbook, but not without good reason (and a good story).

As the tale goes, many decades ago Grandpa’s work friend came over for dinner with his wife. Grandma – who had a long career as a home economics teacher – entertained them and made one of her standard guests-are-coming-over meals. After the meal, the friend’s wife handed Grandma a cookbook. An autographed cookbook.

The work friend’s wife was none other than Marion Rombauer Becker, one of the co-authors of The Joy of Cooking. Grandma had no idea until after the meal, and her autographed copy of that book remains a family treasure. Grandma joked for years that she would have made a much fancier dinner if she had known who they were hosting!

Whenever my husband’s family references this cookbook, it’s never by the title – The Joy of Cooking is simply known to them as “Mrs. Becker’s”.

While this French onion soup could be served as a main dish, we usually use it as an appetizer. It goes great with a large slice of Reuben casserole.

Ingredients

One bonus about this French onion soup recipe: it can easily be prepared in a vegetarian or vegan manner. While the traditional recipe utilizes beef broth – and shines with homemade beef bone broth – it still tastes delightful when you instead use vegetable broth. The key is making sure you include copious amounts of garlic and herbs in the broth.

If you’re making vegan French onion soup, also make sure you substitue oil for the listed butter, and you use a vegan cheese substitute instead of traditional shredded cheese in the topping.

2 tablespoons butter (substitute oil if preparing in a vegan manner)
2 tablespoons neutral oil
8 small (or 5-7 medium) onions, sliced thin
½ cup dark beer – I like to use Guinness Extra Stout for the rich, malty flavor, but you’re welcome to use whatever is cheap and available.
3 tablespoons minced garlic
1/2 teaspoon dried sage
1/2 teaspoon dried thyme
4 cups vegetable or beef broth
2 teaspoons salt (only if using unsalted broth or stock)
1 cup shredded cheese (Ideally Swiss or Gruyere, but mozzarella also works)
6 slices of crusty bread (I prefer day-old sourdough)

How to make French onion soup

Start by melting the butter over medium heat. Once the butter has melted, add the additional neutral oil. Why so much fat? We are going to be caramelizing these onions, and we need to start with a solid base. Next, add the sliced onions and sauté.
After 10 min of cooking, add garlic to the onions and continue to sauté. The onions should be starting to caramelize.

After 20-25 minutes of cooking, add ¼ cup of dark beer to the onion mixture. Allow to cook down for an additional 10 minutes before adding the remaining spices and again deglazing the pan with another ¼ cup of dark beer.

After 40-60 minutes of cooking, the onions will have sufficiently caramelized. Add broth and bring to a boil.

Reduce heat to low and allow the soup to simmer for 20-30 minutes. Add salt and pepper to taste.

Once ready to serve, transfer the soup to a heatproof bowl. Top with croutons or a slice of your favorite crusty bread.

Sprinkle each bowl of French onion soup with a small handful of Swiss or Gruyere cheese.

Place bowls on a baking sheet and broil on “high” until the cheese has slightly caramelized. Serve immediately.

Whether you’re making it traditional, vegetarian, or vegan, I hope you enjoy this French onion soup recipe as much as our family has! If you make it at home, feel free to leave a message in the comments below, or to tag @WhiskAverseBaking in any pictures of your creation you post on social media. Don’t forget to click the “Pin Recipe” button to save this soup for later.