From cozy Parisian bistros to your very own kitchen, French Onion Soup delivers pure comfort in every spoonful. This classic recipe transforms humble onions into a rich, deeply flavorful broth that’s topped with crusty bread and bubbling cheese.
Ready in just 1 hour and 35 minutes, this hearty soup offers the perfect balance of caramelized sweetness and savory depth. With 27g of protein and generous portions of vitamins A and C, it’s not just soul-warming – it’s nourishing too.
Ingredients Section
- Onions: 1½ pounds thinly sliced (about 3 large onions)
- Butter: 3 tablespoons for cooking + 4 tablespoons melted for bread
- Seasonings: ¼ teaspoon each of sugar and salt
- Flour: 2 tablespoons all-purpose, helps thicken the soup
- Liquids: 6 cups low-sodium beef broth, ½ cup white wine
- Aromatics: ½ teaspoon dried thyme, 2 bay leaves, small chunk of celery
- Bread: 8 slices French Baguette
- Garlic: 2 cloves, halved for rubbing
- Cheese: 1 cup Gruyere and ⅓ cup Parmesan, freshly grated
Instructions Section
- Caramelize Onions: Melt butter with onions over medium heat, season lightly. Add sugar and cook until golden brown (25 minutes). Keep heat moderate to avoid burning.
- Make Base: Stir in flour and cook 3 minutes. Add broth, wine, thyme, celery, and bay leaves. Simmer partially covered for 30 minutes.
- Toast Bread: Brush baguette slices with melted butter, toast at 350°F for 15 minutes, flipping halfway. Rub with fresh garlic.
- Final Assembly: Remove bay leaves and celery. Pour soup into oven-proof bowls, top with toasted bread and both cheeses.
- Broil: Place under high broil until cheese turns golden brown and bubbly.
Mastering Caramelized Onions
The magic of French onion soup lies in perfectly caramelized onions. Take your time with this step – rushing won’t do you any favors! Keep the heat steady at medium-low and stir now and then. You’ll notice the onions slowly turn from white to golden to a rich brown color.
This slow cooking (about 25 minutes) brings out their natural sweetness. If you see them getting too dark in spots, lower the heat a bit and add a splash of water.
Cheese Selection Tips
While Gruyere is the classic choice for French onion soup, you can play around with other options. Swiss cheese makes a great substitute, melting just as beautifully. If you can’t find Gruyere, try a mix of Swiss and mozzarella.
The key is picking a cheese that melts well and has a nice flavor without being too strong. The parmesan adds a lovely salty kick that brings everything together!
Make-Ahead & Storage
The soup base (without the bread and cheese) keeps wonderfully! You can make it up to 3 days ahead and store it in the fridge. Just warm it up when you’re ready to serve, then add your toasted bread and cheese toppings.
You can also freeze the base for up to 3 months – just skip the bread and cheese until serving day. The flavors actually get better after a day or two as everything mingles together!
Serving Success
Serve this soup piping hot – that’s when it’s at its best! Pick bowls that can handle the heat of your broiler. The best part is breaking through that crusty cheese top into the steamy soup below.
A simple green salad on the side makes this a complete meal. Don’t forget to put out extra napkins – that melty cheese can get a bit stringy (but that’s part of the fun)!
French Onion Soup
Equipment
- Large pot
- Baking sheet
- Oven-proof bowls
Ingredients
- 1 1/2 pounds onions (about 3 large onions), thinly sliced
- 3 Tablespoons butter
- 1/4 teaspoon granulated sugar
- 1/4 teaspoon salt
- 2 Tablespoons all-purpose flour
- 6 cups low-sodium beef broth
- 1/2 cup white wine
- 1/2 teaspoon dried thyme
- 1 piece celery just a small chunk, not the whole rib
- 2 bay leaves
- 8 slices French Baguette
- 4 Tablespoons butter melted
- 2 cloves garlic halved
- 1 cup Gruyere cheese fresh grated
- 1/3 cup parmesan cheese freshly grated
Instructions
- Add butter and onions to a large pot over medium heat. Season with a little salt and pepper and cook until softened. Add sugar and continue to gently stir until onions become golden brown and caramelized, about 25 minutes. Careful to not let them burn! Maintain a medium to medium-low heat.
- Add the flour and cook for 3 more minutes.
- Add beef stock, wine, thyme, celery, and bay leaves. Cook partially covered for 30 minutes.
- Preheat oven to 350 degrees F.
- Arrange bread on a baking sheet and brush with melted butter on both sides. Bake for 15 minutes, flipping to the other side half way through. Remove from oven and rub a cut clove of garlic onto each piece of bread.
- Turn oven to High broil. Remove bay leaves and the piece of celery from the soup and ladle soup into 4 oven proof bowls.
- Place the toasted bread on top of each bowl. Depending on the size of your bowls you may need two slices of bread. Sprinkle the tops generously with both types of cheese. Broil until the cheese is browned and bubbling.
