The Best Homemade Onion Soup Recipe

I’ve always been drawn to the simplicity of onion soup and how it transforms humble ingredients into something deeply comforting. Getting the onions just right—soft, golden, and caramelized—is key. Once you add the broth and wine, the flavors meld into something rich and complex. There’s also the finishing touch of melted cheese on top that takes it to another level. If you’ve never made it from scratch, you’re in for a treat.

Recipe

This homemade onion soup recipe will blow your mind—it’s rich, deeply flavorful, and tastes like it came straight from a French bistro. The secret? Slowly caramelizing the onions until they’re golden and jammy, a technique that transforms humble ingredients into something magical.

Add a splash of white wine and a savory broth base, and you’ve got a soup that’s both comforting and luxurious. Top it with a slice of crusty bread and melted Gruyère cheese, and you’ll understand why this dish is a timeless classic.

Trust me, once you try this version, you’ll never go back to store-bought. It’s perfection in a bowl.

Ingredients

For a truly unforgettable homemade onion soup, selecting the right ingredients is key. While the recipe is simple, the quality and type of ingredients can make all the difference in achieving that rich, deeply flavorful broth caramelized onions are known for. Here’s what you’ll need, along with some insider tips and easy swaps to make your soup shine.

• Yellow onions: 4 large. These are the star of the show—their high sugar content caramelizes beautifully, creating a sweet, savory base. Red or white onions can work in a pinch, but yellow onions are non-negotiable for the best flavor.
• Unsalted butter: 4 tablespoons. Butter adds richness and helps caramelize the onions. If you’re out of butter, olive oil can substitute, but the taste will be slightly different.
• Beef broth: 6 cups. This is the backbone of the soup’s flavor. Use homemade if possible, or opt for a high-quality store-bought version. Vegetable broth works for a lighter alternative.
• Dry white wine: 1 cup. Adds depth and acidity. Skip it if you must, but a splash of white wine vinegar diluted with water can mimic the flavor.
• Fresh thyme: 4 sprigs. Essential for that herbal note. Dried thyme (1 teaspoon) can substitute, but fresh is ideal.
• Bay leaves: 2. A must-have for their subtle, aromatic flavor. Don’t skip these—they’re the secret to a complex broth.
• Salt and freshly ground black pepper: To taste. Season well throughout the cooking process to layer flavors.
• Baguette: 1 loaf, sliced. Perfect for that crispy, toasty topping. Any crusty bread will do, but a baguette’s texture is ideal.
• Gruyère cheese: 1 ½ cups, grated. The classic choice for its nutty, melty perfection. Swiss or provolone can substitute, but Gruyère is worth the splurge.

Optional but recommended: A splash of cognac or brandy (about 1 tablespoon) added after caramelizing the onions adds an extra layer of sophistication.

Garlic (2 cloves, minced) can also be sautéed with the onions for a bolder flavor. Little touches like these elevate your soup from good to gourmet.

How to Make the Best Follow Precise Ingredient Measurements

• Slice onions evenly: Thin, uniform slices guarantee even caramelization. Pro tip: Use a mandoline slicer for precision, but be careful with your fingers!
• Caramelize onions slowly: Cook onions over medium-low heat with butter and olive oil. Stir occasionally for 30-40 minutes until they turn deep golden brown. Patience is key—rushing this step can burn the onions.
• Deglaze with wine: Add white or red wine to scrape up the flavorful browned bits from the pan. Pro tip: Use a dry wine for a balanced flavor, and let it simmer until reduced by half.
• Add broth and herbs: Pour in beef or vegetable broth and toss in thyme and bay leaves. Simmer for 20 minutes to let flavors meld. Avoid boiling—gentle simmering preserves the soup’s delicate taste.
• Season thoughtfully: Taste and adjust salt and pepper just before serving. Pro tip: Add a splash of Worcestershire sauce for a hint of umami depth.
• Finish with toasted bread and cheese: Ladle soup into oven-safe bowls, top with a slice of toasted baguette, and sprinkle grated Gruyère or Parmesan. Broil for 2-3 minutes until bubbly and golden. Watch closely—cheese can burn quickly!
• Serve immediately: Enjoy hot, with a sprinkle of fresh parsley or thyme for a vibrant touch. Pro tip: Let the bowls cool slightly before serving to avoid burns.

Note: This recipe is flexible—use vegetable broth for a vegetarian version or add a splash of sherry for extra richness.

Nutrition

Onion soup is a classic dish rich in flavor and nutrients. Below is the nutritional breakdown per serving.

Chef Tips

While making onion soup, I’ve found that caramelizing the onions slowly over low heat is key to releasing their natural sweetness and depth.

I always use a mix of yellow and red onions for a balanced flavor.

Adding a splash of white wine or sherry elevates the broth.

Finally, I toast the bread lightly before placing it on top to avoid sogginess.