The first time I tasted Brennan’s French onion soup in New Orleans, I knew immediately that this was not the version I had grown up with. It was richer, smoother, and deeply satisfying without being heavy. Each spoonful lingered just a bit longer, with a luxurious texture that felt almost silky.
When our server explained that Brennan’s finishes their soup with egg yolk and cream instead of wine or sherry, everything clicked. This subtle but brilliant technique transforms a humble onion soup into something elegant while letting the sweetness of the onions shine. It is comfort food with unmistakable New Orleans refinement.
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What makes Brennan’s French Onion Soup so good?Â
Brennan’s Restaurant has been a pillar of New Orleans dining since 1946, known for blending classic French techniques with Creole sensibility. Their French onion soup reflects that philosophy perfectly.
Instead of relying on wine for depth, Brennan’s uses a traditional French liaison made from egg yolk and cream. This method thickens the soup naturally and creates a velvety mouthfeel that coats the palate without masking flavor. The result is rich yet balanced, indulgent yet unmistakably onion-forward.
Why you should try this recipe
This recipe uses technique rather than excess ingredients to achieve depth and richness. Slowly caramelized onions build natural sweetness. Beef stock provides a savory backbone. The egg and cream liaison adds body without starch or heaviness.
Skipping wine allows the onions to remain the star of the dish. Paired with crisp bread and melted cheese, every bite delivers contrast between creamy soup, toasted crunch, and savory finish..
Brennan’s French Onion Soup ingredients
For this unique take on French Onion Soup, you’ll need the following:
- Sweet onions – Form the foundation of the soup with their natural sweetness
- Unsalted butter – Provides richness and helps caramelize the onions
- All-purpose flour – Helps thicken the soup slightly
- Beef stock – Creates the savory base of the soup
- Cayenne pepper – Adds subtle warmth and depth
- Salt – Enhances all flavors
- Egg yolk – Creates the unique silky texture that defines this soup
- Heavy cream – Works with the egg yolk to create a luxurious mouthfeel
- French bread – Provides textural contrast as a floating garnish
- Parmesan cheese – Adds savory notes and creates the classic broiled topping
- Breadcrumbs – Offer additional textural contrast when mixed with butter
Ingredient notes and substitutions
With their slightly sweet flavor, Vidalia onions are an excellent choice for making French Onion Soup. Walla Walla onions are another good option. If you can’t find sweet onions, try using white onions with a pinch of sugar.
Substituting light or half-and-half for the heavy cream in this recipe won’t work. You need the fat content to thicken the soup without separating.
Substituting olive oil for the butter won’t work either. You need the butter’s creaminess and flavor.
You can swap croutons or sauteed breadcrumbs for slices of French bread if you prefer.
If desired, you can substitute the Parmesan cheese with Swiss or Gruyere.
Add two bay leaves to the soup for additional flavor. Remember to remove them before serving the soup.
How to make Brennan’s French Onion Soup
To prepare Brennan’s French Onion Soup:
- Cut the onions into paper-thin slices. Use a mandolin if you have one; just be careful and use the food guard that came with it.
- Melt the butter in a large soup pot on the lowest setting on your stove. Add the onions and stir well to coat in the butter.
- Cook the onions over very low heat until they start to break down. Stir occasionally.Â
- Sprinkle the flour over the onions and stir it in.
- While the onions are cooking, melt butter in a small bowl in the microwave. Add the bread crumbs and stir to coat with the melted butter.
- Transfer the bread crumbs to a small oven-safe dish, and bake for about 10 to 12 minutes, until they begin to brown and become fragrant. Remove from the oven and set aside
- Continue to cook and stir the onions for 10 to 15 more minutes, then pour in the beef stock and add the cayenne pepper and salt. Â
- Bring the soup to a boil and reduce it to a simmer for 15 more minutes. Stir from time to time.
- While the soup is simmering, whisk the egg and heavy cream together in a small bowl—reserve for later.Â
- Remove the pot from the heat.
- Temper the egg and cream mixture by adding a few tablespoons of the hot soup to the bowl while whisking. Raising the temperature will help prevent the egg from scrambling when you add it to the rest of the soup.
- Pour the warmed egg and cream mixture into the soup pot and stir well. This step, called a Liaison Finale in French, quickly thickens soups and sauces without adding starch.
- You can keep the soup warm in a soup kettle, crock pot, or over low heat.
- To serve, preheat the oven to broil and ladle the soup into oven-safe bowls. Place the bowls on a baking sheet.
- Float slices of French bread on the soup, and top the rounds with Parmesan cheese and buttered bread crumbs. Melt the cheese under the broiler flame.
- If desired, garnish the soup with fresh thyme leaves or other fresh herbs.
What to serve with this soup
This soup is pretty rich, so it’s a good idea to pair it with something that’s on the lighter side. An entree salad is a great choice; perhaps a Cobb salad, spinach salad with warm bacon dressing, wedge salad with blue cheese dressing, or Chicken Caesar salad. Baked white fish or poached fish is also a good option.
If you are really hungry, then go ahead and make a classic Steak Frites for an authentic French experience.
Storage and reheating instructions
This soup is best enjoyed the same day it is made. The egg and cream may separate when reheated.
If preparing ahead, stop before adding the egg and cream. Add the liaison only when ready to serve.
To reheat finished soup, thin with beef stock and warm gently while stirring constantly.
Brennan’s French Onion Soup with Egg and Cream
Ingredients
- 16 ounces butter divided use
- 4 cups sliced onions
- 1 cup bread crumbs
- 1 3/4 cups all-purpose flour
- 12 cups beef stock
- 1/2 teaspoon cayenne pepper
- 1 1/2 tablespoons salt
- 1 egg yolk
- 2 tablespoons cream
- 8 slices French bread toasted
- ½ cup grated Parmesan cheese
Instructions
- In a 6-quart soup pot, melt 12 ounces of butter. Add the onions and reduce the heat to very low, ensuring that the onions do not brown. Cook until the onions have caramelized.
- While the onions are cooking, preheat the oven to 350°F.
- Melt 4 ounces of butter in a small bowl in the microwave for about 30 seconds on high power. Add the bread crumbs and stir to coat with the melted butter. Transfer the bread crumbs to a small oven-safe dish, and bake for about 10 to 12 minutes, until they begin to brown and become fragrant. Remove from the oven and set aside.
- When the onions have caramelized, add the flour to the pot and cook for 5 to 10 minutes, stirring occasionally.
- Add the stock, cayenne, and salt and bring to a boil. Reduce the heat and simmer for about 15 minutes. Remove the pot from the heat.
- Beat the egg yolk and cream in a small bowl. Add a little of the soup to the bowl and mix quickly. Then add the egg mixture to the soup pot.
- Ladle the soup into small bowls, place a piece of toasted French bread over each bowl, and sprinkle with the grated Parmesan cheese and buttered bread crumbs. Place the bowls under the broiler until the cheese melts and begins to brown. Serve immediately.
Nutrition
More Brennan’s Copycat Recipes
Love onion soup? Try these great recipes!
- Applebee’s French Onion Soup
- Panera French Onion Soup
- Onion Soup Gratinée
- Outback Creamy Onion Soup
- TGI Friday’s French Onion Soup
Favorite Soup Recipes
- Chicken Gnocchi Soup
- Chili’s Chicken Enchilada Soup
- Cream of Celery Soup
- Creamy Vegetable Soup
- Panera Autumn Squash Soup
Check out my easy soup recipes and the best copycat restaurant recipes on CopyKat!
Just finished a wonderful bowl of this soup. Was easy to follow the instructions and this is a keeper!
Again I love onion soup! This one looks good I’ll have to try it!