French Onion Soup America’s Test Kitchen Recipe

French Onion Soup is a timeless comfort food that has been delighting taste buds for centuries. Rich, savory, and deeply aromatic, this dish combines caramelized onions, a flavorful broth, and gooey melted cheese over a crusty slice of bread. Though the origins of this iconic dish trace back to France, it has found a home in kitchens worldwide, with variations across cultures and chefs putting their spin on it. But no matter where it’s made, the essentials are the same: sweet, tender onions, savory broth, and that glorious, cheesy topping.

America’s Test Kitchen is known for its rigorous testing and perfecting of recipes, so when they present a French Onion Soup recipe, you know it’s going to be a balanced masterpiece. What makes their version stand out is its emphasis on technique, simplicity, and deep, layered flavors. In this detailed exploration, we’ll walk you through everything from ingredients to expert tips, giving you all the tools you need to master this classic at home.

French Onion Soup America’s Test Kitchen Recipe

If you’re aiming to recreate the kind of French Onion Soup that’s served at top-notch bistros, America’s Test Kitchen’s version is a perfect starting point. It’s designed to maximize the natural sweetness of the onions while ensuring the broth is both rich and well-seasoned, without being overly salty or greasy. The recipe also includes tips for making sure the cheese melts perfectly without losing its texture.

Here’s the breakdown of how to make this iconic soup:

Ingredients Needed

Before you jump into the cooking process, make sure you’ve got everything you need. The beauty of French Onion Soup is that the ingredients are simple, but the quality of each element is crucial for achieving that perfect balance of flavor. Here’s what you’ll need:

• 4 to 6 large yellow onions – These form the heart of the soup, and their sweetness, which develops through slow caramelization, will bring out the deep, savory flavors of the broth.
• 4 cups low-sodium beef broth – Beef broth is the traditional choice, giving the soup a rich, meaty foundation. Low-sodium ensures you can control the salt content.
• 2 cups water – The additional water helps to dilute the broth slightly and balance out the intense flavors, making the soup more drinkable and less concentrated.
• 1 tablespoon unsalted butter – For sautéing the onions and giving them that extra layer of richness.
• 2 tablespoons olive oil – This adds a nice fat to the soup without overpowering the flavors, helping to create a smooth texture.
• 2 teaspoons fresh thyme leaves – Fresh thyme adds a fragrant, earthy element that complements the caramelized onions beautifully.
• 1 bay leaf – A subtle aromatic note to elevate the broth.
• 1/2 cup dry white wine – A splash of wine provides acidity to balance the sweetness of the onions.
• 1/2 teaspoon sugar – Optional, but if you’re aiming to speed up the caramelization process of the onions, a little sugar can help.
• Salt and pepper – Essential for seasoning and enhancing all the flavors.
• 8 slices of French bread or baguette – Stale or toasted, these slices form the base of the soup, soaking up the broth and turning golden and crispy when baked.
• 2 cups grated Gruyère cheese – The crowning glory! Gruyère is known for its nutty, slightly salty flavor, and it melts beautifully into the soup for that classic golden, bubbly topping.

Cooking Instructions

Making French Onion Soup is a labor of love, but the process is straightforward if you follow these steps:

1. Caramelize The Onions

   • Heat a large Dutch oven or heavy pot over medium heat. Add the butter and olive oil, allowing them to melt and combine.
   • Add the sliced onions and sprinkle with a pinch of salt. Cook, stirring occasionally, for about 45 minutes. The key is to cook the onions slowly, allowing them to soften and turn golden brown. If needed, add a splash of water to prevent burning.

2. Deglaze With Wine

   • Once the onions have fully caramelized, pour in the white wine, scraping up any browned bits from the bottom of the pot. Let the wine reduce by half, which will help concentrate the flavor.

3. Add The Broth

   • Stir in the beef broth, water, thyme, bay leaf, and sugar (if using). Bring the soup to a simmer, then reduce the heat to low. Let the soup cook for another 30 minutes, allowing all the flavors to meld together.

4. Prepare The Bread

   • While the soup simmers, preheat the oven to 400°F (200°C). Place the bread slices on a baking sheet and toast in the oven for about 10 minutes, until golden and crispy.

5. Assemble The Soup

   • Discard the bay leaf and season the soup with salt and pepper to taste. Ladle the soup into oven-safe bowls. Place a slice of toasted bread on top of each bowl, and sprinkle with a generous amount of grated Gruyère cheese.

6. Broil Until Bubbly

   • Set the bowls under the broiler for 3-5 minutes or until the cheese is melted, bubbly, and golden brown.

7. Serve

   • Remove the bowls from the oven (be careful, they’ll be hot!). Serve immediately and enjoy.

Ingredient Insights

• Onions: Yellow onions are the most common choice for French Onion Soup because of their balance of sweetness and sharpness. As they cook, they develop a deep, sweet flavor that gives the soup its signature taste. While red onions are occasionally used for color, yellow onions are the preferred choice for their complexity and depth.
• Gruyère Cheese: Gruyère is a hard Swiss cheese known for its ability to melt smoothly without separating. It also has a slightly nutty flavor that complements the sweetness of the onions. Some recipes call for a mix of Gruyère and Parmesan, but the classic French Onion Soup leans heavily on Gruyère for its creamy texture.
• Beef Broth: The type of broth you use is crucial to achieving a well-rounded soup. America’s Test Kitchen recommends low-sodium beef broth for a deeper flavor without excessive saltiness, which allows you to adjust the seasoning to taste. You can also make your own broth for a more homemade touch.

Expert Tips

1. Don’t Rush the Onion Caramelization: Patience is key when caramelizing onions. The slow process is what brings out the deep, sweet flavors. If you turn the heat too high, the onions will burn and become bitter. You want them golden brown, not charred.
2. Use Stale Bread: Fresh bread can become soggy too quickly. Use slightly stale or toasted bread to get that perfect balance between crunch and soaking up the soup.
3. Thickening the Soup: If you prefer a thicker soup, you can add a small amount of flour when cooking the onions to help thicken the broth.
4. Broiling the Cheese: Keep an eye on the cheese as it broils. It melts quickly and can go from perfectly bubbly to burnt in a flash.

Recipe Variations

While the classic version is hard to beat, there are a few variations you can try:

• Vegan French Onion Soup: Swap the beef broth for a hearty vegetable broth, use vegan butter and cheese, and you’ve got a vegan version that still delivers on flavor.
• Add Herbs: If you want to change up the flavor profile, add a sprig of rosemary or sage while simmering the broth. These herbs add a nice earthiness to the soup.
• Cheese Variations: Experiment with different cheeses, like Swiss or Fontina, if you prefer a milder or creamier taste.
• Wine Substitute: If you don’t have white wine, a dry sherry can be a great substitute, adding a slightly different flavor complexity to the broth.

Final Words

French Onion Soup is a beautiful dish that rewards those who put in the effort. Whether you’re cooking it for a cozy weeknight dinner or for a special occasion, this recipe from America’s Test Kitchen will give you a foolproof guide to making a restaurant-worthy soup at home. The balance of flavors, textures, and aromas is sure to make every spoonful feel like a warm hug.