Classic French Onion Soup Recipe

If you’ve ever wished you could bottle up the charm of a cozy Parisian bistro, this Classic French Onion Soup is your answer! With sweet caramelized onions, rich beef broth, and a crown of gooey, golden cheese, this iconic bowl delivers soul-warming comfort and irresistible French flavor with every bubbly spoonful.

Ingredients You’ll Need

Every silky, savory bowl of Classic French Onion Soup starts with surprisingly simple ingredients, but each one plays a starring role—bringing sweetness, depth, and that signature melty top to life. Here’s the cast of characters you’ll need to make your soup shine.

• Sweet Onions (3 lbs): The backbone of this dish—when caramelized, they become sweet, jammy, and full of soul-warming richness.
• Unsalted Butter (6 tablespoons): Butter helps the onions reach golden perfection, lending the base irresistible flavor and a gorgeous glossy finish.
• All Purpose, Unbleached Flour (3 tablespoons): Just a touch thickens the broth slightly and gives the soup its lovely, velvety texture.
• Red Wine (1 cup): Adds depth and a subtle fruity acidity that balances the sweetness of the onions—use something you’d happily sip.
• Beef Stock (8 cups): Rich, meaty broth is essential for that traditional French bistro flavor; quality counts here.
• Bay Leaves (2) & Fresh Thyme (4 sprigs): These classic herbs infuse gentle aromatics that round out each spoonful—don’t skip!
• Salt and Pepper: Bring everything together with just the right seasoning to taste.
• Baguette (1, thinly sliced): Toasted and popped on top, the crusty bread soaks up broth and holds that luscious cheese.
• Gruyère Cheese (1 1/2 cups, grated): Melty, nutty, golden perfection—no Classic French Onion Soup is complete without it!

Variations

One of the best things about Classic French Onion Soup is how easy it is to tailor it to your needs! Whether you’re looking for a vegetarian tweak, a gluten-free option, or a little extra something for the cheese lovers, there’s a way to make this classic uniquely yours.

• Vegetarian-Friendly: Substitute quality vegetable broth (and skip the Worcestershire, if adding) for a meatless but still deeply satisfying soup.
• Gluten-Free: Swap the all-purpose flour for your favorite gluten-free flour blend, and use GF bread for the topping.
• Cheese Lovers’ Dream: Try a blend of Gruyère and Emmental, or even a little sharp provolone, for a different cheesiness atop your soup.
• White Wine Twist: Use dry white wine in place of red for a slightly lighter, brighter flavor profile.

How to Make Classic French Onion Soup

Step 1: Caramelize the Onions

In a large heavy pot, melt the unsalted butter over medium heat. Add all your thinly sliced sweet onions and let them slowly soften, occasionally stirring so nothing burns. This stage takes patience—about 30 minutes—but you’ll know you’re there when the onions are deeply golden, jammy, and your kitchen smells absolutely amazing.

Step 2: Add the Flour and Wine

Sprinkle the flour over the onions and cook for about one minute, just until it’s absorbed and slightly toasted. Pour in the red wine, scraping up any flavorful browned bits from the pot—this brings out even more depth. Let it simmer until most of the wine has evaporated, concentrating those delicious flavors.

Step 3: Simmer with Broth and Herbs

Add the beef stock, bay leaves, and thyme sprigs, and bring everything to a gentle boil. Reduce the heat back down and let your soup bubble slowly for about 30 minutes, allowing the flavors to marry and concentrate. Remove the bay leaves and thyme, then season generously with salt and pepper.

Step 4: Toast the Baguette

While the soup simmers, preheat your broiler and brush baguette slices with a touch of olive oil. Set them on a baking sheet and broil until golden and crisp—about 2 to 3 minutes. This little detail helps your bread stay sturdy and soak up just the right amount of broth without falling apart.

Step 5: Assemble and Broil

Ladle the hot soup into oven-safe bowls, tuck in one or two toasted baguette slices, and absolutely bury them in a blanket of grated Gruyère. Place the bowls on a baking sheet and broil just until the cheese is melting, bubbly, and gorgeously golden—watch carefully, as this magic happens fast!

Step 6: Finish and Serve

Let the bowls cool for just a couple of minutes (that cheese gets molten!), then garnish with a scatter of fresh thyme for a pop of color and aroma. Serve right away and soak up the oohs and aahs—you’ve just made Classic French Onion Soup that rivals any restaurant!

How to Serve Classic French Onion Soup

Garnishes

The crowning touch for Classic French Onion Soup is, of course, that generous mound of melted Gruyère, but don’t hesitate to add a sprinkle of fresh thyme or chopped chives for a bright, herbaceous pop. A little cracked black pepper or even a light drizzle of high-quality olive oil right before serving adds a lovely final flourish!

Side Dishes

Pair your bowl with a crisp, lemony salad, a platter of roasted veggies, or more slices of baguette for dunking bliss. I love serving Classic French Onion Soup alongside a simple green salad tossed in Dijon vinaigrette or a charcuterie board for the ultimate French bistro spread at home.

Creative Ways to Present

Classic French Onion Soup shines in rustic, oven-safe crocks, but you can also assemble mini portions in ramekins for a gourmet appetizer. Try serving in wide-mouthed mugs for a more casual vibe, or top with heart-shaped baguette toasts for a special occasion like date night at home.

Make Ahead and Storage

Storing Leftovers

Let any leftover soup cool to room temperature, then transfer to airtight containers and refrigerate for up to four days. Leave out the bread and cheese until you’re ready to reheat and serve, so everything stays fresh and at its best.

Freezing

Classic French Onion Soup freezes beautifully (minus the bread and cheese topping). Pour cooled soup into freezer-safe containers or zip bags, leaving an inch of space for expansion, and freeze for up to three months. Thaw overnight in the fridge before reheating.

Reheating

Reheat soup gently on the stovetop over medium-low, stirring often. When hot, ladle into oven-safe bowls, add fresh toasted baguette and cheese, then broil until bubbly—just like when it was first made!

FAQs

Final Thoughts

If you’re ready for a touch of French magic at your own table, this Classic French Onion Soup is calling your name. Grab a crusty baguette, a hunk of Gruyère, and a pot of patience—your most comforting, flavor-packed bowl ever is just around the corner. Bon appétit, friends!

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