Cozy French Onion Soup Gratinée Recipe

There is nothing quite like the deep aroma of slowly caramelized onions filling the kitchen on a crisp evening. I find that making this French Onion Soup Gratinée is just as comforting as eating it.

You might think restaurant quality soup is hard to achieve at home, but patience is really the only secret ingredient. My version delivers that savory broth and cheesy topping you crave without any complicated techniques.

Why You’ll Love This French Onion Soup Gratinée

The rich combination of sweet onions and savory beef stock creates a depth of flavor that feels incredibly luxurious. I love how the acidity from the vinegar cuts through the richness to add a perfect sophisticated note.

That golden crust of bubbly Gruyère cheese over toasted bread offers the ultimate texture contrast to the silky soup underneath. Every spoonful gives you a bit of crunch, gooey cheese, and warm broth.

This recipe actually tastes even better the next day as the flavors have more time to meld together. You can easily prepare the soup base ahead of time and just broil the toasts right before serving.

If you enjoyed this warm bowl of comfort, you will definitely want to try my Ultimate Short Rib Stuffed Shells Recipe for another hearty meal. The Cozy Garlic Butter Steak Bites Recipe also pairs wonderfully with these flavors for a complete dinner experience.

Everything You Need for Perfect French Onion Soup Gratinée

Here is what you will need to gather from the pantry and fridge:

• Yellow Onions: These provide the essential balance of savory and sweet notes when caramelized down slowly.
• Butter: I use unsalted butter to help the onions brown evenly and add a rich, creamy mouthfeel to the base.
• Beef Stock: You want a high-quality, robust stock to provide the savory backbone that defines this soup.
• Sugar: A small amount helps aid the caramelization process and highlights the natural sweetness of the onions.
• All-Purpose Flour: This acts as a thickener to give the broth just enough body without making it heavy.
• Apple Cider Vinegar: I use this as a non-alcoholic substitute for sherry to deglaze the pan and add necessary brightness.
• Extra Beef Broth: Used in place of wine for deglazing to keep the liquid volume correct while adding flavor.
• Dried Thyme: The earthy, floral notes of thyme are the perfect herbal companion to the sweet onions.
• Kosher Salt: Essential for drawing moisture out of the onions and seasoning the final broth.
• Black Pepper: Freshly ground pepper adds a gentle heat that cuts through the rich cheese and butter.
• French Baguette: A sturdy bread that can hold up to the broth while providing a crispy foundation for the cheese.
• Gruyère Cheese: This is the classic choice for its superior melting quality and distinct nutty flavor profile.
• Fresh Thyme: I like to garnish with fresh sprigs for a pop of color and a burst of herbal aroma.

My Method for Perfect French Onion Soup Gratinée

Let’s get cooking and fill your home with amazing smells:

1. Start by melting the butter in a large Dutch oven or a heavy-bottomed pot over medium heat to ensure even cooking. Add your sliced yellow onions to the pot and toss them to coat evenly in the butter. Sprinkle the sugar over the onions, as this helps kickstart the browning process and deepens the flavor profile. Cook the onions slowly, stirring frequently to prevent burning, until they turn a deep golden brown and become very soft. This process requires patience and should take about one hour to achieve the perfect French Onion Soup Gratinée base.
2. Once the onions are beautifully caramelized, sprinkle the flour over them and stir constantly for about one minute to cook off the raw flour taste. Pour in the apple cider vinegar and the extra portion of beef broth to deglaze the pan, scraping up any browned bits from the bottom. Add the remaining beef stock and the dried thyme to the pot. Bring the mixture to a gentle simmer and cook partially covered for about 30 minutes to allow all the rich flavors to marry together. Season generously with salt and fresh black pepper to suit your taste.
3. While the soup simmers, preheat your oven broiler to get it ready for the final step. Arrange the baguette slices in a single layer on a baking sheet. Place them under the broiler for a minute or two until they are toasted to a light golden brown on both sides. Watch them closely during this step because bread can burn very quickly under high heat. Set the toasted slices aside until you are ready to assemble the bowls.
4. To serve, ladle the hot soup into oven-safe bowls or crocks, leaving a little room at the top. Place two slices of the toasted bread directly onto the surface of the soup in each bowl. Generously sprinkle the grated Gruyère cheese over the bread, allowing some to spill over the edges if you like that rustic look. Place the bowls on a baking sheet and broil for a few minutes until the cheese is melted, bubbly, and browned in spots. Garnish with fresh thyme sprigs immediately before serving.

My Best Tips for Perfect French Onion Soup Gratinée

Do not try to rush the caramelization process by turning up the heat too high on your French Onion Soup Gratinée base. Low and slow cooking allows the natural sugars to develop without burning the onions.

Since broth makes up the majority of this dish, I highly recommend using the best quality beef stock you can find or making your own. A rich stock ensures your French Onion Soup Gratinée has that restaurant-quality depth.

Make sure to toast your baguette slices thoroughly before placing them on top of the liquid. This extra step prevents the bread from getting soggy too quickly once it hits the French Onion Soup Gratinée.

Best Ways to Enjoy French Onion Soup Gratinée

I like to serve this French Onion Soup Gratinée alongside a crisp green salad with a sharp vinaigrette to balance the richness. It also works beautifully as a starter for a steak dinner or roast chicken.

If you prefer to keep your bread crispy, you can broil the cheesy toasts on a separate baking sheet. Simply place them on top of the French Onion Soup Gratinée right at the table.

I love seeing what you make, so please follow me on Pinterest to keep up with my latest recipes.

French Onion Soup Gratinée

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• Author: Amelia Bryan
• Total Time: 1 hr 45 min
• Yield: 6 servings
• Diet: None

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Description

A comforting, savory soup featuring deeply caramelized onions, rich beef broth, and a decadent topping of toasted baguette and melted Gruyère cheese.

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Ingredients

• 1 Tbsp. Sugar
• 4 Tbsp. Butter
• 1/2 Cup Extra beef broth (for deglazing)
• 3/4 Tsp. Dried thyme
• 1 Tbsp. Apple cider vinegar
• 2 Lbs. Yellow onions, halved and thinly sliced
• 12 Oz. Gruyère cheese, grated
• 1 Tbsp. All-purpose flour
• 6 Cups Beef stock
• 12 slices French baguette (3/4-inch thick)
• Fresh Thyme sprigs for garnish
• Kosher salt and freshly ground black pepper to taste

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Instructions

1. Melt the butter in a large pot or Dutch oven over medium heat. Add the sliced onions and sprinkle with sugar. Cook slowly, stirring often, for about 55-65 minutes until the onions are soft and deep golden brown.
2. Sprinkle the flour over the caramelized onions and stir for 1 minute. Add the apple cider vinegar and the extra beef broth to deglaze the pan, scraping up browned bits.
3. Pour in the remaining beef stock and add the dried thyme. Bring to a simmer and cook partially covered for 25-30 minutes. Season with salt and pepper.
4. Preheat your broiler. Place baguette slices on a baking sheet and toast under the broiler until golden brown on both sides.
5. Ladle the soup into oven-safe bowls. Top each with two slices of toasted bread and a generous amount of grated Gruyère cheese.
6. Broil the bowls on a baking sheet for 2-3 minutes until the cheese is melted, bubbly, and browned. Garnish with fresh thyme and serve hot.

Notes

This recipe uses apple cider vinegar and extra broth instead of the traditional sherry to keep it alcohol-free while maintaining excellent flavor.

• Prep Time: 10 min
• Broiling: 5 min
• Cook Time: 1 hr 35 min
• Category: Soup
• Method: Stovetop/Broil
• Cuisine: French

Nutrition

• Serving Size: 1 bowl
• Calories: 480
• Sugar: 9g
• Sodium: 1100mg
• Fat: 28g
• Saturated Fat: 16g
• Unsaturated Fat: 10g
• Trans Fat: 0g
• Carbohydrates: 35g
• Fiber: 3g
• Protein: 22g
• Cholesterol: 75mg

Keywords: French Onion Soup Gratinée, homemade onion soup, easy soup recipe, cozy dinner, caramelized onions