Mary Berry​ French Onion Soup Recipe

This rich Mary Berry French Onion Soup is made with plenty of sliced onions, butter, beef stock, dry white wine, and a splash of brandy. The result is a deeply flavorful, comforting, and savory bowl of soup with a sweet caramelized taste. It is the perfect starter for a dinner party or a cozy main meal on a cold winter night, making enough for 6 people.

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Mary Berry French Onion Soup Ingredients

For the Soup:

• 2 oz (50g) butter
• 1 tbsp olive oil
• 2 lbs (900g) large onions (peeled and thinly sliced)
• 1 tsp sugar
• 2 cloves garlic (crushed)
• 2 tbsp all-purpose flour
• 7 cups (1.5 liters) beef stock (hot)
• 1 cup (250ml) dry white wine
• 2 tbsp brandy (optional)
• Salt and black pepper to taste

For the Cheesy Toasts (Croutons):

• 1 French baguette (sliced into rounds)
• 1 tsp Dijon mustard
• 1 ½ cups (150g) Gruyère cheese (grated)

How To Make Mary Berry French Onion Soup

1. Soften the onions: Melt the butter and oil in a large, deep pot over medium heat. Add the sliced onions and cover with a lid. Cook gently for about 15 minutes until the onions are soft.
2. Caramelize the onions: Remove the lid and turn the heat up slightly. Stir in the sugar. Cook for another 20 minutes, stirring often, until the onions turn a deep golden brown color. This step creates the sweet flavor.
3. Add thickener and liquid: Stir in the crushed garlic and flour. Cook for 1 minute. Gradually pour in the hot beef stock and white wine while stirring constantly to prevent lumps.
4. Simmer the soup: Bring the mixture to a boil. Reduce the heat, cover, and let it simmer gently for about 45 minutes. Stir occasionally.
5. Add finishing touches: Stir in the brandy (if using) and season with salt and pepper.
6. Prepare the cheesy toasts: While the soup finishes, toast the baguette slices under a broiler (grill) on one side. Turn them over, spread a little Dijon mustard on the untoasted side, and pile on the grated Gruyère cheese. Broil until the cheese is melted and bubbly.
7. Serve: Ladle the hot soup into bowls and float one or two cheesy toasts on top.

Recipe Tips

• Don’t Rush the Onions: The most important step is browning the onions. If you rush this, the soup will lack that deep, rich color and sweet flavor. Let them cook until they are truly golden brown.
• Use Good Stock: Since this soup has very few ingredients, the quality of your beef stock matters. Use a high-quality store-bought stock or homemade stock for the best taste.
• The Mustard Trick: Mary Berry’s secret is spreading Dijon mustard on the toast before adding the cheese. It adds a sharp, tangy kick that cuts through the richness of the soup.
• Slice Evenly: Try to slice your onions to the same thickness. This ensures they cook evenly so you don’t end up with some burnt pieces and some raw pieces.

What To Serve French Onion Soup

This soup is quite rich because of the butter and cheese. If you serve it as a main course, pair it with a crisp green salad with a vinaigrette dressing to refresh your palate. If you are serving it as a starter, follow it with a lighter main dish, such as roasted chicken or poached fish, so the meal isn’t too heavy.

How To Store French Onion Soup Leftovers

• Refrigerate: Store the soup base (without the cheesy toasts) in an airtight container in the refrigerator for up to 3 days. Store the bread separately to prevent it from getting soggy.
• Freeze: This soup freezes very well. Let the soup cool completely, then freeze it in a freezer-safe container for up to 3 months. Thaw it in the fridge overnight before reheating. Make fresh cheesy toasts when you are ready to serve.

Mary Berry French Onion Soup Nutrition Facts

Serving Size: 1 bowl (with crouton)

• Calories: 380 kcal
• Total Fat: 18g
• Saturated Fat: 10g
• Cholesterol: 45mg
• Sodium: 850mg
• Total Carbohydrate: 32g
• Dietary Fiber: 3g
• Sugars: 9g
• Protein: 14g

Frequently Asked Questions

• Can I make this alcohol-free? Yes. You can replace the white wine and brandy with extra beef stock. You can also add a teaspoon of Worcestershire sauce or a splash of vinegar to add some acidity.
• What allows the onions to brown? The natural sugars in the onions, combined with the added teaspoon of sugar, help them caramelize. Removing the lid in step 2 is crucial because it lets the steam escape so the onions fry rather than steam.
• Can I use a different cheese? Gruyère is traditional because it melts well and has a nutty flavor. If you cannot find it, you can use Comté, Emmental, or a sharp mature Cheddar cheese.

Try More Recipes:

• Mary Berry Minestrone Soup​ Recipe
• Mary Berry​ Watercress Soup Recipe
• Mary Berry Pea And Mint Soup​ Recipe