Delia Smith French Onion Soup​ Recipe

This rich Delia Smith French Onion Soup is made with plenty of thinly sliced onions, butter, good quality beef stock, dry white wine, and crispy homemade garlic croutons. The result is a deeply savory and comforting bowl of soup topped with bubbling, melted Gruyère cheese. It is a perfect starter for a dinner party or a cozy main meal on a cold winter night, serving about 6 people.

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Delia Smith French Onion Soup Ingredients

For the Soup:

• 1 1/2 lb (700 g) onions, thinly sliced
• 2 tablespoons olive oil
• 2 oz (50 g) butter
• 2 cloves garlic, crushed
• 1/2 level teaspoon granulated sugar
• 2 pints (1.2 liters) good beef stock
• 10 fl oz (275 ml) dry white wine
• 2 tablespoons Cognac (optional)
• Salt and freshly milled black pepper

For the Garlic Croutons:

• French bread or baguette, cut into 1 inch (2.5 cm) diagonal slices
• 1 tablespoon olive oil
• 1-2 cloves garlic, crushed

For the Topping:

• 8 oz (225 g) Gruyère cheese, grated

How To Make Delia Smith French Onion Soup

1. Prepare the croutons: Preheat your oven to a moderate heat. Drizzle 1 tablespoon of olive oil onto a baking sheet and spread the crushed garlic over it. Press the bread slices into the oil on both sides. Bake for 20-25 minutes until they are crispy and crunchy.
2. Sauté the onions: In a large saucepan or casserole dish, melt the butter and 2 tablespoons of oil over high heat. Add the onions, crushed garlic, and sugar. Cook for about 6 minutes, stirring often, until the edges of the onions turn dark.
3. Caramelize the mixture: Reduce the heat to the lowest setting. Let the onions cook very slowly for about 30 minutes. The base of the pan should be covered with a rich, nut-brown caramelized film.
4. Simmer the soup: Pour in the beef stock and white wine. Season with salt and pepper. Stir with a wooden spoon, scraping up the caramelized bits from the bottom of the pan. Bring to a simmer, then cover and cook gently for about 1 hour.
5. Add the finishing touches: Just before serving, bring the soup back to a simmer. Taste and adjust seasoning. If it is a cold night, stir in the Cognac.
6. Broil and serve: Warm your soup bowls. Ladle the hot soup into the bowls and float the croutons on top. Sprinkle a thick layer of grated Gruyère cheese over the croutons. Place the bowls under a hot grill (broiler) until the cheese is golden and bubbling. Serve immediately.

Recipe Tips

• Don’t Rush the Onions: The secret to the rich flavor is the slow cooking of the onions. Allow them the full 30 minutes on low heat to develop that deep, caramelized color.
• Scrape the Pan: When you add the liquid, make sure to scrape the bottom of the pot. The brown film on the bottom holds the most intense flavor.
• Use Good Stock: Since the broth is simple, the quality of your beef stock matters. Use a high-quality store-bought version or homemade stock for the best results.
• Warn Your Guests: The soup bowls and the liquid inside will be extremely hot after coming out from the broiler. Let them sit for a minute before eating.

What To Serve French Onion Soup

This soup is quite rich and filling, so it pairs best with lighter sides. A crisp green salad with a sharp vinaigrette helps cut through the richness of the cheese and onions. If you are serving this as a main course, you can offer extra crusty baguette on the side for dipping. For a full French bistro experience, follow the soup with a simple steak frites or roasted chicken.

How To Store French Onion Soup Leftovers

• Refrigerate: Store the soup base (without the bread and cheese topping) in an airtight container in the refrigerator for up to 3-4 days. Store the croutons separately in a bag at room temperature.
• Freeze: This soup freezes very well. Let the soup cool completely, then store it in a freezer-safe container for up to 3 months. Do not freeze the soup with the bread or cheese added.

Delia Smith French Onion Soup Nutrition Facts

Serving Size: 1 bowl (approx. 1/6 of recipe)

• Calories: 480 kcal
• Total Fat: 28g
• Saturated Fat: 14g
• Cholesterol: 70mg
• Sodium: 950mg
• Total Carbohydrate: 25g
• Dietary Fiber: 3g
• Sugars: 8g
• Protein: 18g

Frequently Asked Questions

• Can I leave out the wine and Cognac? Yes, you can makes this soup alcohol-free. Simply replace the wine and Cognac with an equal amount of extra beef stock or water with a splash of vinegar for acidity.
• What is the best cheese to use? Gruyère is the classic choice because it melts beautifully and adds a nutty flavor. If you cannot find it, Comté, Emmental, or a sharp white cheddar are good substitutes.
• Can I make this soup ahead of time? Yes, French Onion Soup actually tastes better the next day as the flavors meld. Make the soup base a day in advance, reheat it, and add the croutons and cheese just before serving.

Try More Recipes:

• Delia Smith Celery Soup​ Recipe
• Delia Smith Cauliflower Soup​ Recipe
• Delia Smith Carrot And Leek Soup Recipe