Classic French Onion Soup (Printable)

Savory French soup with caramelized alliums in beef broth, topped with cheesy toast.

# Ingredient list:

→ Alliums

01 - 4 large yellow onions, thinly sliced
02 - 2 large leeks, white and light green parts only, cleaned and thinly sliced
03 - 3 shallots, thinly sliced
04 - 3 garlic cloves, minced

→ Fats

05 - 3 tablespoons unsalted butter
06 - 2 tablespoons olive oil

→ Broth & Umami

07 - 8 cups high-quality beef broth
08 - 1 tablespoon Worcestershire sauce
09 - 2 teaspoons soy sauce
10 - 1/2 cup dry white wine
11 - 2 teaspoons fresh thyme leaves
12 - 1 bay leaf

→ Bread & Cheese

13 - 1 baguette, sliced into 1/2-inch rounds
14 - 2 cups Gruyère cheese, grated
15 - 1/2 cup Parmesan cheese, grated

→ Seasonings

16 - Salt and freshly ground black pepper, to taste

# How-to:

01 - In a large heavy-bottomed pot or Dutch oven, heat the butter and olive oil over medium heat until shimmering.
02 - Add the sliced onions, leeks, and shallots. Sauté, stirring frequently, until very soft and deep golden brown, approximately 35 to 40 minutes.
03 - Add the minced garlic and cook for 2 minutes more, stirring constantly.
04 - Pour in the dry white wine while scraping the bottom of the pot with a wooden spoon to release caramelized browned bits.
05 - Stir in the beef broth, Worcestershire sauce, soy sauce, thyme, and bay leaf. Bring to a simmer over medium-high heat.
06 - Reduce heat to low and cook uncovered for 30 minutes, stirring occasionally until flavors meld.
07 - Season with salt and freshly ground black pepper to taste. Remove and discard the bay leaf.
08 - Preheat the oven broiler to high setting.
09 - Arrange baguette slices on a baking sheet and toast under the broiler until golden brown, approximately 1 to 2 minutes per side.
10 - Ladle the hot soup into oven-safe bowls. Top each with toasted baguette slices and a generous amount of grated Gruyère cheese.
11 - Place bowls under the broiler until the cheese is melted and bubbly, approximately 3 to 5 minutes.
12 - Remove from broiler and serve immediately, garnished with fresh thyme if desired.

# Expert Advice:

01 -
  • The umami depth sneaks up on you in the best way, making a simple onion soup taste impossibly complex and restaurant-worthy.
  • It actually gets better the next day when all those flavors have settled into each other like old friends.
  • There's real magic in watching that melted cheese bubble under the broiler, and your guests will be genuinely impressed.
02 -
  • The caramelizing step is not negotiable and cannot be rushed, no matter how hungry you are or what the clock says.
  • Using truly good broth is worth the extra dollar or two because it's honestly the foundation of whether this soup tastes like a French bistro or tastes like sadness.
  • The Gruyère has to be real Gruyère if you can get it, because that nutty, slightly sharp flavor is what makes people close their eyes when they taste it.
03 -
  • Make the soup up through the simmering step the day before and refrigerate it, then just reheat and finish with the bread and cheese topping when you're ready to serve.
  • If you want extra depth, add a splash of dry sherry or brandy along with the white wine, but don't tell people it's there, just let them taste the mystery.
  • Sometimes I add a small splash of balsamic vinegar at the very end, just enough that nobody can identify it but everyone says the flavor is somehow deeper.
Return