Name: French Onion Soup
Prep time: 15 min
Cook time: PT-487359H34M41S
Total time: PT-487359H34M41S
Cuisine: French
Ingredients: 4 large onions, thinly sliced; 2 tablespoons olive oil or vegan butter; 1 teaspoon sugar; 4 cups vegetable broth; 1 cup dry white wine (optional); 1 teaspoon dried thyme; Salt and pepper to taste; Baguette slices for topping; Vegan or traditional shredded cheese

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A warm, comforting pot of French Onion Soup, slow-cooked to bring out the rich sweetness of caramelized onions. I love how this method makes the flavors deep and mellow, offering a cozy, satisfying meal.

French Onion Soup

Why You’ll Love This Recipe

I adore this soup because it transforms humble ingredients into something luxuriously flavorful. The onions cook down to a sweet, golden depth, then simmer with broth and wine for a savory balance. Topped with baguette and melted cheese, it becomes a warm, indulgent treat that’s perfect any time I need comfort food.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

4 large onions, thinly sliced
2 tablespoons olive oil or vegan butter
1 teaspoon sugar
4 cups vegetable broth
1 cup dry white wine (optional)
1 teaspoon dried thyme
Salt and pepper to taste
Baguette slices for topping
Vegan or traditional shredded cheese

Directions

Add the sliced onions, olive oil (or vegan butter), and sugar to the crockpot.
Cook on high for 4–5 hours or on low for 8–10 hours, stirring occasionally, until the onions are deeply caramelized.
Add vegetable broth, white wine (if using), thyme, salt, and pepper. Cover and cook on low for 1–2 hours.
Preheat the broiler.
Ladle the soup into oven-safe bowls, top each with a baguette slice, and sprinkle with shredded cheese.
Broil for 2–3 minutes until the cheese is melted and bubbly.
Serve hot and enjoy the savory, cheesy goodness!

Servings and timing

This recipe makes about 4–6 servings.

Prep time: 15 minutes (mostly slicing onions).
Cook time: 5–12 hours (slow-cooking onions) + 1–2 hours simmering + broiling time, around 2–3 minutes.
Total time: If I use high heat, roughly 6–7 hours; on low, it’s closer to 9–13 hours.

Variations

I sometimes skip the wine and add a splash of apple cider vinegar for tang.
For a richer broth, I’ll use part mushroom broth or add a splash of soy sauce or vegan Worcestershire.
I can mix cheeses—Gruyère or cheddar for traditional, or dairy-free mozzarella blend for a vegan twist.
A pinch of smoked paprika adds a lovely smokiness.
Fresh thyme or rosemary can replace dried for a brighter herby note.

Storage/reheating

I store leftover soup in an airtight container in the fridge for up to 4 days. To reheat, I warm it gently on the stove until simmering. If adding bread and cheese, I reheat in oven-safe bowls under the broiler to recreate that bubbly topping. For freezing, I separate the soup (without bread) into freezer-safe containers for up to 3 months, then thaw overnight in the fridge before reheating.

FAQs

What onions work best for French Onion Soup?

I usually use yellow onions for their balanced sweetness and savory flavor. Sweet onions like Vidalia work too, but can make it milder.

Can I make this on the stovetop instead of a crockpot?

Absolutely! I can caramelize onions in a pot over medium-low heat for about an hour, then proceed with the broth and simmer for 30–45 minutes.

How do I prevent the soup from being too salty?

I start with low-sodium broth and taste as I go. The cheese and bread add salt, so I adjust seasoning right before serving.

What if I don’t have a broiler?

I simply place the topped bowls under a very hot oven (450 °F or 230 °C) for a few minutes until the cheese melts.

Can I make this dairy-free and vegan?

Yes! I use vegan butter or oil, plant-based broth, and a vegan cheese alternative—my favorite is a melty vegan mozzarella blend.

Conclusion

I love how this French Onion Soup elevates simple ingredients into something rich, comforting, and a bit indulgent. Slow cooking the onions is worth the wait—it rewards me with depth and sweetness that shines through every spoonful. Whether I follow the traditional route or customize it vegan-style, it’s always a hit. Give it a try and savor every cheesy, caramelized bite!