Traditional French Onion Soup is a simple yet extremely delicious dish made with caramelized onions braised in flavorsome Homemade Beef Stock. Topped with crispy and cheesy baguette slices, this soup makes a perfect starter for a dinner party or warming comfort food for cold winter nights.
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This delicious French Onion Soup doesn't require many ingredients and it is very easy to make at home when you follow a few key steps. All you need is some patience when caramelizing the onions, pretty much like when caramelizing onions for Hyderabadi Mutton Biryani!
I adapted this authentic French Onion Soup recipe (the same as I adapted other French recipes on my blog such as Moules Mariniere - French Mussels and French Strawberry Custard Tart) from my Le Cordon Bleu Cookery School book and made a few changes to simplify it.
The key ingredient is a good homemade beef stock which is flavored with caramelized onions, smoked bacon, bay leaves, vermouth, and thyme for perfection!
What Is Traditional French Onion Soup?
French Onion Soup is probably one of the most famous soups in the world. It is one of these fancy-looking dishes we tend to order in a restaurant because we think it is difficult to make it at home.
A Traditional French Onion Soup is made with caramelized onions slowly braised in a good homemade beef stock flavored with vermouth (or sherry), bay leaves, and thyme.
The addition of a piece of smoked bacon gives a slight smokiness to the French Onion Soup so I strongly advise using it.
This onion soup is best when served with a slice of crusty baguette that is covered with melty, delicious Gruyère cheese mixed with some good quality Parmesan.
What Onions are Best for French Onion Soup?
The two main ingredients of a good French Onion Soup are onions and homemade beef stock.
I use mainly yellow onions with the addition of some red onions.
Yellow onions have a rich onion taste and they become sticky and sweet when caramelized. Red onions have a sharp and deep flavor and less sweetness.
If you find your soup too sweet, increase the number of red onions and use fewer yellow onions.
Ingredients and Substitutes
- Onions - I use a mixture of yellow onions and red onions. You can adjust the ratio of the yellow onions to red ones to balance the sweetness of your onion soup. If you find it too sweet, simply use more red onions.
- Beef stock - A good quality homemade beef stock is essential for a rich and flavorsome French Onion Soup. Store-bought ones usually lack flavor and richness which will leave you with a blend and weak soup. Use homemade Chicken Stock instead if you find making your own beef stock time-consuming. Or if you really want to use store-bought beef stock, try buying the best one.
- Bacon - A whole smoked bacon is added to the soup for a slightly smoky flavor. You can omit it if you prefer so.
- Vermouth - You can substitute vermouth with sherry. Skip the alcohol if you are cooking for kids or for a non-alcoholic version.
- Butter - It adds flavor to this Traditional French Onion Soup, and also helps caramelize the onions.
- Flour - Plain flour (all-purpose flour) adds body and thickens the onion soup.
Garnish for French Onion Soup
- Cheese - Gruyère is the main cheese to use for this Traditional French Onion Soup recipe. I add freshly grated parmesan as it adds a nutty, salty flavor that develops a tasty crust under the broiler.
- Baguettes - I use homemade sourdough baguettes but shop-bought baguettes are perfectly fine too.
- Garlic - Rubbing the baguette slices with garlic adds a hint of garlic taste without overpowering the soup.
How to Make the Perfect French Onion Soup?
French Onion Soup is a simple recipe that requires a bit of patience while caramelizing the onions. However, you need to follow a few simple steps to achieve the best results:
Caramelize the Onions
To make the soup, start by slicing your onions. Try to slice them finely for perfect and quick caramelization.
Place a Dutch oven or a heavy-based pan on low heat and add the butter.
When the butter melts, add the sliced onions to the pan.
Gently cook the onions until nice and soft, stirring occasionally to avoid them burning. That usually takes around 15 minutes.
When they are soft and translucent, turn the heat up to medium-high to start the caramelization.
Keep stirring the onions to avoid burning them and be patient at that stage.
We need nice golden brown color on onions without burning them. Burnt onions will give a bitter taste and unpleasant look to the soup.
If the onions aren't caramelized enough, the soup will lack the sweetness coming from the onions.
Build the Soup
When the onions are golden brown and release their sweetness, add the garlic and cook for another minute.
Use vermouth or sherry to deglaze the pan then add the flour.
Give it a good stir then deglaze the pan again with some of the beef stock to dissolve all the brown bits stuck to the surface.
Add the whole bacon, bay leaves, thyme, and black pepper along with some more of the beef stock. Only add just enough stock to make a thick soup. You can always add more later if it's too thick at the end of the cooking period.
Bring it to a boil, turn the heat to low, and let it gently simmer for 45 minutes.
Garnish the Soup and Serve
Preheat the grill to 200° C (390° F) and start preparing your garnish while the soup is cooking.
Thinly slice the baguette, rub them with garlic, and place them in the oven for a few minutes until lightly toasted.
When the soup is cooked, remove the whole bacon, bay leaves, and thyme stalks. Check the seasoning and add some salt if needed.
Ladle the soup in individual oven-proof bowls or ramekins.
Put a slice (or two!) of baguettes on top of the soup, top them with your cheese mixture, and place the ramekins in the oven. Let them under the grill until the cheese is bubbly and slightly golden.
If you don’t have oven-proof individual bowls or ramekins, you can grill the cheesy baguettes separately on a tray and place them on soup ladled in bowls.
Scroll down to the recipe card for the full, printable recipe!
What to Serve With Traditional French Onion Soup?
You can serve this delicious and rich soup as an appetizer for special occasions or gatherings such as Thanksgiving or Christmas dinner parties. This recipe would serve 6 guests when served as a starter/appetizer.
If you want to serve it as a main dish, you can serve it along with a bowl of simple salad such as Coban Salatasi (Turkish Shepherd's Salad), Rocket and Parmesan Salad, or Gavurdagi Salatasi (Tomato and Walnut Salad).
Top Tips From The Chef
- If you find your soup too sweet, increase the number of red onions and use fewer yellow onions.
- A good quality homemade beef stock is essential for a rich and flavorsome French Onion Soup.
- Try to slice the onions finely for perfectly even and quick caramelization.
- Cook the onions slowly and patiently until the natural sugars are released, and the onions are transparent and have a deep golden brown color. Do the caramelizing without burning them. Burnt onions will give a bitter taste and unpleasant look to the soup.
- Using a wide heavy-based pan will help caramelize the onions evenly and also help reduce the caramelizing time.
Recipe FAQs
Let the soup totally cool down and place it in an airtight container without the cheese and baguettes. You can keep the leftover onion soup for up to 5 days refrigerated or up to 3 months in the freezer.
When ready to serve, place the refrigerated soup in a pan on a stovetop and bring it to a boil. You can also microwave it for 2 minutes on medium power, stirring it halfway through.
When the soup is heated thoroughly, pour it into individual oven-safe bowls, top with a slice of baguette, and grated Gruyère and parmesan. Place under the broiler/oven grill until the cheese is bubbly and perfectly browned. Serve immediately.
The best option for Traditional French Onion Soup is Gruyère cheese mixed with a bit of Parmesan. However, you can use other hard cheeses such as Provolone, Gouda, Fontina, and Swiss cheeses.
Related Recipes
For more delicious French recipes why not try:
Did you make this recipe? Please let me know how it turned out! Leave a comment below and tag @cookingorgeous on Instagram and hashtag it #cookingorgeous.
I hope you enjoy the process of making this simple yet incredibly flavourful French Onion Soup as much as you enjoy eating it! 🙂
Bon appétit! / Afiyet olsun!
Traditional French Onion Soup
Equipment
Ingredients
For the Soup
- 50 g butter
- 100 g red onion (finely sliced)
- 400 g yellow onion (finely sliced)
- 1 clove garlic (finely chopped)
- 50 ml vermouth or sherry
- 25 g plain flour
- 750 ml beef stock
- 15 g smoked bacon
- 2 bay leaves
- 3 sprigs thyme
- ¼ teaspoon freshly ground black pepper
- salt to taste
For the Garnish
- 1 baguette
- 1 clove garlic (cut in half)
- 100 g Gruyère cheese (finely grated)
- 50 g Parmesan cheese or any hard Italian cheese (finely grated)
Instructions
Caramelizing the Onions
- To make the soup, start by slicing your onions. Try to slice them finely for perfect and quick caramelization.
- Place a Dutch oven or a heavy-based pan on low heat and add the butter.
- When the butter melts, add the sliced onions to the pan.
- Gently cook the onions until nice and soft, stirring occasionally to avoid them burning. That usually takes around 15 minutes.
- When they are soft and translucent, turn the heat up to medium-high to start the caramelization.
- Keep stirring the onions to avoid burning them and be patient at that stage. We need nice golden brown color on onions without burning them. Burnt onions will give a bitter taste and unpleasant look to the soup. If the onions aren't caramelized enough, the soup will lack the sweetness coming from the onions.
Building the Soup
- When the onions are golden brown and release their sweetness, add the garlic and cook for another minute.
- Use vermouth or sherry to deglaze the pan, and then add the flour.
- Give it a good stir then deglaze the pan again with some of the beef stock to dissolve all the brown bits stuck to the surface.
- Add the whole bacon, bay leaves, thyme, and black pepper along with some more of the beef stock. Only add just enough stock to make a thick soup. You can always add more later if it's too thick at the end of the cooking period.
- Bring it to a boil, turn the heat to low, and let it gently simmer for 45 minutes.
Garnishing the Soup and Serving
- Preheat the grill to 200° C (390° F) and start preparing your garnish while the soup is cooking.
- Thinly slice the baguette, rub them with garlic, and place them in the oven for a few minutes until lightly toasted.
- When the soup is cooked, remove the whole bacon, bay leaves, and thyme stalks. Check the seasoning and add some salt if needed.
- Ladle the soup in individual oven-proof bowls or ramekins.
- Put a slice (or two!) of baguettes on top of the soup, top them with your cheese mixture, and place the ramekins in the oven.
- Let them under the grill until the cheese is bubbly and slightly golden.
- If you don’t have oven-proof individual bowls or ramekins, you can grill the cheesy baguettes separately on a tray and place them on soup ladled in bowls.
Notes
- If you find your soup too sweet, increase the number of red onions and use fewer yellow onions.
- A good quality homemade beef stock is essential for a rich and flavorsome French Onion Soup.
- Try to slice the onions finely for perfectly even and quick caramelization.
- Cook the onions slowly and patiently until the natural sugars are released, and the onions are transparent and have a deep golden brown color. Do the caramelizing without burning them. Burnt onions will give a bitter taste and unpleasant look to the soup.
- Using a wide heavy-based pan will help caramelize the onions evenly and also help reduce the caramelizing time.
- This recipe would serve 6 guests when served as a starter/appetizer.
Nutrition
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Danilo
The whole family enjoyed these flavors and this soup is a family favorite a great recipe and will make again!