🥇 1. The Secret to Great French Onion Soup (Most People Rush This)

🧅 Classic French Onion Soup | Supermarket to Sizzle
In this episode of Supermarket to Sizzle, we turn simple supermarket ingredients into a rich, restaurant-quality French Onion Soup.
This classic bistro dish is built on slowly caramelized onions, good beef broth, fresh herbs, toasted baguette, and a generous layer of nutty Gruyère cheese melted under the broiler until bubbling and golden.
The secret to incredible French onion soup is patience. Slowly cooking the onions brings out their natural sweetness and deep flavor, creating a broth that tastes complex and comforting with very simple ingredients.
In this recipe you’ll learn:
• How to properly caramelize onions
• Why wine is used to deglaze the pan
• How herbs like thyme and bay leaves add depth
• Why Gruyère is the classic cheese for French onion soup
• How to get the perfect bubbling cheese top under the broiler
🛒 Ingredients
Ingredient US Metric
Large yellow onions, thinly sliced 7 onions ~1.8–2 kg
Unsalted butter 4 tbsp 56 g
Olive oil 1 tbsp 15 ml
Garlic, minced 4 cloves 4 cloves
All-purpose flour 2 tbsp 16 g
Dry white wine (for deglazing) ½ cup 120 ml
Beef broth 8 cups 1.9 L
Fresh thyme sprigs (tied together) 3 sprigs 3 sprigs
Bay leaves 2 2
Kosher salt to taste
Fresh black pepper to taste
Baguette, sliced 1 loaf 1 loaf
Gruyère cheese, grated 8–10 oz 225–285 g
👨‍🍳 Step-by-Step Instructions
1. Caramelize the Onions
Thinly slice the onions.
In a large soup pot or Dutch oven, melt the butter and olive oil over medium heat.
Add the onions and a pinch of salt.
Cook slowly for 35–45 minutes, stirring occasionally, until the onions become deep golden brown and caramelized.
This step develops the sweet, rich flavor that defines French onion soup.
2. Build the Flavor Base
Add the minced garlic and cook for about 30 seconds until fragrant.
Sprinkle in the flour and stir for 1–2 minutes to remove the raw flour taste and slightly thicken the soup.
3. Deglaze the Pan
Pour in the ½ cup dry white wine (120 ml).
Scrape the bottom of the pot to release all the flavorful browned bits from the onions.
Allow the wine to simmer for 2–3 minutes until slightly reduced.
4. Add Broth and Herbs
Pour in the 8 cups beef broth (1.9 L).
Add:
3 thyme sprigs
1 rosemary sprig
2 bay leaves
Bring the soup to a gentle simmer.
Cook for about 1 hour, allowing the flavors to fully develop.
Season with salt and black pepper to taste.
Remove the herb bundle and bay leaves before serving.
5. Toast the Bread
Preheat oven to 375°F / 190°C.
Slice the baguette into ¾–1 inch (2–2.5 cm) slices.
Place on a baking sheet and toast for 8–12 minutes, flipping halfway, until lightly crisp.
6. Assemble the Soup
Ladle the hot soup into oven-safe bowls.
Place a toasted slice of baguette on top of each bowl.
Generously cover with grated Gruyère cheese.
7. Broil Until Bubbling
Place the bowls under the broiler on the top rack.
Broil for about 4 minutes, or until the cheese is fully melted, bubbling, and golden brown.
Watch carefully so the cheese doesn’t burn.
🍽️ What Makes French Onion Soup Special
A great French onion soup should have:
• Deep savory flavor from the broth
• Sweet, jammy caramelized onions
• Aromatic herbs in the background
• Toasted bread soaking up the soup
• Nutty, bubbling Gruyère cheese on top
The result is a comforting bowl of soup that tastes like it came straight from a French bistro.
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