Homemade French Onion Soup is much easier to prepare than it looks. The only step that requires patience is caramelizing the onions, and while it takes time, it’s simple: low heat and occasional stirring will transform sweet onions into a deeply flavored base. After that, the process is mostly simmering the broth and topping each bowl with toasted bread and melted cheese under the broiler. The result is a rich, comforting soup with a golden, bubbly cheese crust that feels both elegant and satisfying.
French Onion Soup
This is one of the coziest soups for cold weather. Caramelized onions simmered in a combination of beef and chicken broth, brightened with a splash of wine and a touch of thyme, become a deeply flavorful base. Each serving is finished with a crisp round of toasted baguette and a generous layer of aged Swiss cheese, broiled until bubbly and golden. It’s an approachable recipe that makes an impressive bowl for family dinners or a casual get-together.
Give yourself time to caramelize the onions fully—rushing that step sacrifices the savory, sweet depth that defines classic French onion soup. The broiled cheese is the crowning touch; it converts a simple soup into an irresistible, indulgent comfort dish.
Why You’ll Love This Dish
- Make-Ahead Friendly – The soup stores and reheats very well, making it ideal for leftovers.
- Rich, Layered Flavor – Slow-cooked onions plus wine and mixed broths yield deep savory notes.
- Crisp, Cheesy Finish – Toasted baguette and melted aged Swiss add texture and richness.
- Simple Technique – Few complicated steps; most of the time is hands-off simmering or waiting for caramelization.
- Perfect Cold-Weather Comfort – Hearty, warming, and filling without being fussy.
Recipe Shopping List
If you need to shop, here’s everything you’ll want on hand. For exact amounts, see the recipe card below.
- Sweet onions – Large yellow onions or Vidalia are best for a naturally sweet, rich caramelization.
- Salted butter – Helps the onions soften and develop color; don’t skimp on the fat.
- Chicken and beef broth – Using both gives a balanced, full-bodied base.
- White wine – Chardonnay or Pinot Grigio adds brightness.
- Red wine – Cabernet or Pinot Noir contributes depth and structure.
- Ground thyme – A small amount ties the flavors together.
- Aged Swiss cheese – Melts smoothly and adds a nutty finish; Gruyère is an excellent alternative.
- French bread – Sliced and toasted so it holds up under the cheese and in the broth.
How To Make This Recipe
The overview below outlines the main steps. Follow the full recipe card further down for exact measurements and timing while you cook.
- Caramelize the onions: Sauté thinly sliced onions in butter over medium-low heat, stirring occasionally until they’re deep golden and tender—typically 25–30 minutes or more for large batches.
- Build the broth: Transfer the caramelized onions to a large stockpot. Add beef and chicken broth, both wines, and thyme. Taste and season with salt and pepper.
- Simmer: Let the soup cook on medium-low for another 20–25 minutes so the flavors meld.
- Prepare toppings: Preheat the broiler and toast baguette slices until crisp.
- Assemble and broil: Ladle hot soup into oven-safe bowls, top each with a toasted bread round and cheese, then broil until the cheese is melted and bubbly, about 1–3 minutes depending on your broiler.
- Serve immediately: The bowls will be hot—use oven mitts and serve while the cheese is gooey.
Recipe Tips
- Use a wide, heavy-bottomed skillet for even heat distribution while caramelizing.
- Don’t skimp on fat: a little butter helps the onions brown evenly.
- Be patient—good caramelized onions usually take at least 25–30 minutes; larger batches can take longer.
- Avoid constant stirring; brief, occasional stirring lets the onions develop color and fond.
Serve This With
This soup stands well on its own as a satisfying main for a lighter meal. It also works perfectly as part of a soup-and-salad lunch. A crisp green salad with a tangy vinaigrette complements the soup’s richness.
For a multi-course dinner, serve French onion soup as a first course before grilled seafood or steak. It pairs nicely with simply seasoned meats, roasted vegetables, or a side of rice if you want a heartier plate.
Recipe FAQ
How long does French onion soup keep in the fridge?
Store cooled soup in an airtight container in the refrigerator for 3 to 4 days. For longer storage, freeze portions in freezer-safe containers or heavy-duty freezer bags—single-serve portions thaw quickly for a fast lunch. Remember to label frozen containers with the date.
Which onions are best?
Sweet yellow onions or Vidalia are ideal for this soup. Red onions will work but will change the flavor profile slightly.
Can I use only one type of broth?
Yes. Using a combination of chicken and beef produces a balanced depth, but substituting with all beef or all chicken broth is perfectly acceptable based on what you have or prefer.
What cheese works best?
Aged Swiss or Gruyère are classic choices because they melt smoothly and offer a nutty flavor. Provolone or mozzarella can be used in a pinch, though they yield a different character.
French Onion Soup
Hearty French Onion Soup made from caramelized onions, wine, and a blend of broths, topped with crusty toasted baguette and melted aged Swiss cheese.
Prep Time: 10 minutes
Cook Time: 1 hour
Total Time: 1 hour 10 minutes
Ingredients
- 4 large sweet onions, thinly sliced
- 4 tablespoons salted butter
- 4 cups chicken broth
- 4 cups beef broth
- 3/4 cup white wine (Chardonnay or Pinot Grigio)
- 3/4 cup red wine (Cabernet or Pinot Noir)
- 1/4 teaspoon ground thyme
- 12 slices aged Swiss cheese
- 12 slices toasted French bread
Instructions
- Place sliced onions and butter in a large sauté pan over medium-low heat. Cook, stirring occasionally, 25–30 minutes or until onions are deeply caramelized.
- Transfer onions to a large stockpot. Add chicken and beef broths, white and red wine, and thyme. Stir and taste, seasoning with salt and pepper as needed.
- Simmer the soup over medium-low heat for 20–25 minutes to allow flavors to meld.
- While the soup simmers, preheat the broiler and toast the French bread slices until crisp.
- Ladle hot soup into oven-safe bowls, top each with a toasted bread round and two slices of cheese. Place bowls on a baking sheet and broil 1–3 minutes until cheese is melted and bubbly—watch carefully to avoid burning.
- Remove from the oven and serve immediately, using caution as bowls will be hot.
Nutrition Information (per serving)
- Calories: 664
- Total Fat: 21g
- Saturated Fat: 12g
- Trans Fat: 1g
- Unsaturated Fat: 7g
- Cholesterol: 57mg
- Sodium: 1683mg
- Carbohydrates: 71g
- Fiber: 4g
- Sugar: 13g
- Protein: 26g