French Onion Soup: One of the Best Recipes For a Classic Dish

Published by John Polonis on March 22, 2025March 22, 2025

There’s something magical about the aroma of French onion soup filling your home on a cold day. It’s hard to beat the sweet, caramelized scent of slowly cooked onions mingling with a rich broth that permeates throughout the kitchen and house. This combined with the promise of melted cheese atop garlicky, toasted bread creates an atmosphere that’s as comforting as the soup itself.

I recently took on the challenge of making this classic dish, inspired by David Lebovitz’s approachable recipe from “My Paris Kitchen“, with a few personal variations thrown in. I will highlight where I made modifications, and you can find my full recipe at the end of this post.

For the video version of this French onion soup recipe, watch here:

The Star of the French Onion Soup Show: Onions

Let me warn you now—this recipe demands a lot of onion chopping. But that’s to be expected when onions are both the main ingredient and the star of the show. I used 2½ pounds of yellow onions (as David recommended), though white ones would work just as well. As I stood there, knife in hand, I reminded myself that the tears would be worth it for the deeply flavorful result.

There’s something deeply satisfying about slow cooking on a cold day, letting aromas gradually fill every corner of your home. French onion soup delivers this experience in spades—it’s not a dish to be rushed but rather savored in the making.

The Long, Slow Caramelization

The process began simply enough: melting butter in a large pot before adding the mountain of chopped onions. A sprinkle of sugar helped kickstart the caramelization process. After about 20 minutes of cooking, the onions transformed—becoming soft, translucent, and beginning to take on that beautiful caramel color that signals developing flavor.

This is where patience becomes your greatest virtue. The real magic happens during the next hour and a half (minimum) of slow cooking. It’s a lesson in culinary meditation (similar to making sourdough bread!), occasionally stirring to scrape up those flavorful brown bits that collect on the sides and bottom of the pot. Those bits, by the way, are culinary gold; a concentrated flavor that will enrich your soup tremendously.

As the onions gradually darkened and collapsed into a sweet, jammy mixture, I added garlic, salt, and pepper. The aroma alone was worth the effort, and we weren’t even halfway through the process yet.

Building Layers of French Onion Soup Flavor

Once the onions reached that perfect deep caramel state, I stirred in a couple of teaspoons of all-purpose flour—a small but important addition that helps give the soup its slight body. Then came the deglazing step with alcohol.

David Lebovitz’s recipe calls for ¾ cup of white wine, but I had to improvise when I realized I didn’t have any on hand. Digging through my pantry produced a bottle of Chinese cooking wine, which turned out to be an excellent substitute—perhaps even better than the white wine would have been as it’s a heavier and richer flavor than most white wines.

The sizzle as the wine hit the hot pot was satisfying, as was watching it loosen all those flavorful brown bits from the bottom. I then added some homemade chicken stock I had stored in the freezer. Yes, it went in as a giant ice cube, but it quickly melted down as I brought everything to a boil before reducing to a simmer for another 45 minutes.

David Lebovitz suggests an optional step of adding balsamic vinegar to balance the flavor profile, which I tried. That touch of acidity does wonders to brighten the deeply sweet flavors of the caramelized onions. A final adjustment of salt and pepper, and the soup base was complete.

The Crowning Glory

The final assembly is where French onion soup transforms from delicious to spectacular. I ladled the rich, dark broth filled with sweet onions into six oven-safe bowls (including two smaller red ones in the optimistic hope that our three-year-old might be tempted).

For the classic topping, I took some sourdough bread I had on hand, broke it into pieces, and rubbed each side with fresh garlic before placing them atop the soup. Then came the cheese—grated Gruyère, though any Swiss-type cheese works beautifully here. Some people go extremely heavy on the cheese, creating a thick, bubbling blanket, but I prefer a more moderate approach that lets the soup itself remain the star.

Into a 400°F oven they went for about 20 minutes, until the cheese melted and just began to brown on top. You could also use a broiler for this step if your bowls can withstand the direct heat.

The Moment of Truth

There’s something theatrical about serving French onion soup. The bowls emerge from the oven hot (extremely hot—handle with care!), with cheese bubbling around the edges and stretching in long strands with each spoonful. It’s as if you’ve transported a French café directly into your dining room.

The test of any dish, of course, is in the tasting. The flavors were exactly what I’d hoped for—deep, rich, and complex, with the sweetness of the onions balanced perfectly by the savory broth and that hint of acidity. Perhaps the highest praise came from my wife, who—despite not being a big fan of onions—declared it “really good.” For an onion-centered dish to win over an onion skeptic is perhaps the ultimate success.

A Culinary Elevation

This experience reinforced something I firmly believe: humble ingredients can be elevated to extraordinary heights with the right technique and a bit of patience. The onion—often relegated to a supporting role—proves here that it deserves its moment in the spotlight. French onion soup transforms this everyday vegetable into something so comforting and satisfying that it has endured as a classic for generations.

If you’re looking for a cooking project that rewards patience with incredible flavor, French onion soup should be high on your list. The process may be long, but it’s not difficult—just a matter of giving the onions the time they need to slowly transform. The result is well worth every minute spent stirring the pot and every tear shed while chopping.

So the next time you’re craving something deeply comforting and rich with flavor, remember that those humble onions in your pantry have the potential to become something truly spectacular.

For another great recipe, check out my take on Ukrainian Borscht here!

French Onion Soup

This French onion soup begins with slowly caramelizing 2½ pounds of thinly sliced yellow onions in butter with a sprinkle of sugar for about 20 minutes until soft and translucent, then adding garlic, salt, and pepper and continuing to cook for at least 1½ hours. Once the onions have reached a deep caramel color, mix in 2 teaspoons of all-purpose flour, then deglaze with ¾ cup white wine (Chinese cooking wine works as a substitute) before adding chicken stock and simmering for another 45 minutes. For the final touch, ladle the soup into oven-safe bowls, top with garlic-rubbed sourdough bread pieces and a generous sprinkle of Gruyère cheese, then bake at 400°F for about 20 minutes until the cheese is melted and slightly browned. This David Lebovitz-inspired recipe yields 6 servings and takes approximately 3 hours from start to finish, with the lengthy cooking time essential for developing the soup's rich, complex flavor.

Print Recipe Pin Recipe

Prep Time 20 minutes mins

Cook Time 3 hours hrs

Total Time 3 hours hrs 20 minutes mins

Course Appetizer, Side Dish, Soup

Cuisine French

Servings 6 people

Ingredients

  

• 2 1/2 lbs yellow or white onions chopped
• 4 tbsp butter for sauteing onions
• 1 tsp granulated sugar
• pinch salt and pepper to taste
• 2 cloves garlic minced
• 2 tsp all-purpose flour
• 3/4 cup Chinese cooking wine or white wine personally think Chinese cooking wine adds depth to flavor
• 2 liters chicken stock
• 1 tbsp balsamic vinegar add to taste
• 6 pieces sourdough bread
• 1 clove garlic chopped in half, for rubbing on the bread
• 3 cups gruyere or similar cheese any type of swiss cheese works

Instructions

 

Caramelize the onions:

• Melt butter in a large pot
• Add all sliced onions and sugar
• Cook for 20 minutes until onions are soft and translucent
• Add garlic, salt, and pepper
• Continue cooking for at least 1½ hours on low heat, stirring occasionally to scrape up browned bits

Build the soup base:

• Add flour to the caramelized onions and mix well
• Pour in white wine (or Chinese cooking wine like me) to deglaze the pot
• Add chicken stock
• Bring to a boil, then reduce to simmer for 45 minutes
• Add balsamic vinegar (optional) and adjust salt and pepper to taste

Finish the soup:

• Preheat oven to 400°F
• Ladle soup into oven-safe bowls
• Rub both sides of sourdough bread pieces with fresh garlic
• Place bread on top of soup
• Sprinkle generously with grated cheese

Bake:

• Place bowls in the oven, uncovered, for about 20 minutes
• Alternatively, place under broiler until cheese is melted and slightly browned
• Serve immediately (careful – bowls will be very hot!)

Video

Notes

• The long, slow caramelization of the onions is key to developing the deep flavor
• This recipe is inspired by David Lebovitz’s version from “My Paris Kitchen”
• The soup can be made ahead of time and refrigerated; just complete the bread and cheese topping before serving

Keyword Soup