Description
Classic French Onion Soup features deeply caramelized onions simmered in a rich beef stock, infused with aromatic herbs, deglazed with dry vermouth, and topped with toasted French bread slices smothered in melted Gruyere and Parmesan cheese. This comforting soup offers restaurant-quality flavors that you can easily recreate at home, perfect for chilly days or elegant entertaining.
Ingredients
Scale
Onions & Aromatics
- 6 large red or yellow onions (about 3 pounds), peeled and thinly sliced (about 10 cups total)
- 2 cloves garlic, minced
- 1 teaspoon sugar
- Salt, to taste
- 1/2 teaspoon freshly ground black pepper
Fats & Liquids
- 4 tablespoons extra virgin olive oil
- 2 tablespoons butter
- 8 cups beef stock, chicken stock, or a combination (traditionally beef stock)
- 1/2 cup dry vermouth or dry white wine
- 2 tablespoons brandy (optional)
Herbs & Spices
- 2 bay leaves
- 1 tablespoon fresh thyme (or 1/2 teaspoon dried thyme)
Bread & Cheese
- 8 slices French bread or baguette, cut 1-inch thick
- 1 1/2 cups grated Swiss Gruyere cheese
- Sprinkling of grated Parmesan cheese
Instructions
- Peel and slice the onions: Carefully peel the onions and slice them thinly from root to stem to measure about 10 cups. Uniform slicing helps with even caramelization.
- Begin caramelizing the onions: Heat 3 tablespoons of olive oil in a large 5 to 6 quart thick-bottomed pot over medium heat. Add the sliced onions and toss them to coat in the oil. Cook, stirring often, until onions are soft, about 15 to 20 minutes.
- Increase heat and continue caramelizing with butter: Raise heat to medium-high. Add remaining olive oil and butter. Stir frequently until onions begin to brown, between 20 to 40 minutes, depending on your stove and pot. This slow caramelization develops the soup’s deep flavor.
- Add sugar and salt, finish caramelizing, and add garlic: Sprinkle the onions with sugar and salt to encourage caramelization. Continue cooking for another 10 to 15 minutes until deeply browned. Stir in minced garlic and cook for an additional minute to release its aroma.
- Deglaze the pot with vermouth or wine: Pour in the dry vermouth or white wine and scrape up the browned bits stuck to the pot’s bottom and sides. This adds complexity and depth to the soup base.
- Add stock and herbs, then simmer: Add the beef or chicken stock along with bay leaves and thyme. Bring the mixture to a simmer, cover, and reduce heat to maintain a gentle simmer for about 30 minutes to meld flavors.
- Season and optionally add brandy: Taste and adjust seasoning with salt and freshly ground black pepper. Remove the bay leaves. Stir in brandy if desired for a subtle boozy nuance.
- Toast the French bread slices: While soup simmers, preheat oven to 450°F and line a baking sheet with parchment or foil. Brush both sides of the bread slices lightly with olive oil (about 1.5 tablespoons total). Toast in the oven until lightly browned, 5 to 7 minutes.
- Add cheese and melt on the bread: Remove toasted bread from oven, turn over slices, and sprinkle generously with Gruyere and Parmesan cheese. Return bread to oven near serving time and bake until cheese is bubbly and golden brown.
- Serve with cheesy toasts: Ladle soup into bowls or ovenproof dishes. Top each with one cheesy toast. Place under broiler or in a 350°F oven for around 10 minutes until cheese bubbles and browns slightly. Serve immediately and enjoy the rich, comforting flavors.
Notes
- The caramelization of onions is key—be patient to develop a deep, rich flavor.
- Using beef stock yields a more traditional and robust soup, but chicken stock works well for a lighter version.
- Dry vermouth adds great depth, but dry white wine is a good substitute.
- Brandy is optional but enhances flavor with subtle warmth and complexity.
- Gruyere is preferred for its nutty meltability; Parmesan adds an extra savory touch.
- For best results, use a heavy-bottomed pot to ensure even heat distribution and avoid burning.
- Broiling the assembled soup in individual oven-proof bowls creates a dramatic presentation and ensures gooey, bubbly cheese topping.
Nutrition
- Serving Size: 1 serving (about 1 bowl with toast)
- Calories: 699 kcal
- Sugar: 14 g
- Sodium: 1727 mg
- Fat: 26 g
- Saturated Fat: 10 g
- Unsaturated Fat: 16 g
- Trans Fat: 0 g
- Carbohydrates: 84 g
- Fiber: 5 g
- Protein: 30 g
- Cholesterol: 43 mg
