Name: Onion Soup Recipe
Prep time: 15 min
Cook time: 2 h 10 min
Total time: 2 h 25 min
Cuisine: French
Ingredients: 1 large whole garlic head; ½ tablespoon olive oil (for roasting garlic); 1 tablespoon olive oil (for cooking onion and leeks); 9 cups thinly sliced sweet onions (about 4 large); 2 ½ cups sliced leeks (light green and white parts only, about 2 medium); 1 teaspoon salt (divided use); 1 teaspoon dried thyme; 2 tablespoons all-purpose flour; ⅓ cup dry white wine; 4 cups vegetable broth; 2 cups milk; Fresh thyme leaves for garnish; Freshly ground black pepper for garnish

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Introduction

This rich and flavorful caramelized onion soup brings together sweet roasted garlic, slowly cooked onions, and leeks for a comforting bowl of goodness. The combination of roasted garlic and herbs deepens the taste, making it perfect for chilly evenings or as a gourmet starter.

A bowl of smooth, creamy beige soup fills a rustic white bowl resting on a matching white plate with a worn texture. The soup's surface is sprinkled with finely chopped green herbs and small specks of black pepper, creating a simple and fresh topping. A silver spoon held by a woman's hand dips into the soup, lifting a small portion that glistens with a thick, velvety texture. The bowl and plate sit on a soft beige cloth, all placed on a clean white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 large whole garlic head
1 ½ tablespoons olive oil (divided use)
9 cups (about 4 large) thinly sliced sweet onions
2 ½ cups (about 2 medium) sliced leeks (light green and white parts only)
1 teaspoon salt (divided use)
1 teaspoon dried thyme
2 tablespoons all-purpose flour
1/3 cup dry white wine
4 cups vegetable broth
2 cups milk
Fresh thyme leaves for garnish
Freshly ground black pepper for garnish

Instructions

Step 1: Preheat your oven to 350° F. Remove the papery outer skin from the garlic head without separating the cloves. Rub ½ tablespoon olive oil over the garlic, wrap it tightly in foil, and bake for 1 hour. Let it cool for 10 minutes, then separate and peel the cloves. Set the roasted garlic aside in a small dish.
Step 2: Meanwhile, heat the remaining 1 tablespoon olive oil in a large pot over medium heat. Add the sliced onions and leeks and cook uncovered for 30 minutes, stirring often. Add ½ teaspoon salt and the dried thyme, then continue cooking uncovered for another 30 minutes or until the onions turn dark golden brown, stirring occasionally. Add a little water if the onions start to cook too quickly, and scrape any browned bits from the pot’s bottom.
Step 3: Stir the flour into the onion and leek mixture and cook for 1 minute. Pour in the white wine and vegetable broth, bringing the mixture to a boil. Reduce the heat and let it simmer for 30 minutes.
Step 4: Add the roasted garlic cloves and the remaining ½ teaspoon salt into a blender along with half of the onion mixture. Blend until smooth, then repeat with the remaining onion mixture if needed. Pour the blended soup back into the pot.
Step 5: Stir in the milk and simmer gently for 8 minutes until thoroughly heated. Serve hot, garnished with fresh thyme leaves and freshly ground black pepper if desired.

Tips & Variations

For a creamier texture, substitute half of the milk with heavy cream.
If you prefer a deeper flavor, use a splash of sherry instead of white wine.
Vegetarian or vegan cooks can replace milk with unsweetened plant-based milk and ensure the broth is vegetable-based.
Slow cooking the onions longer enhances their sweetness and results in an even richer soup.

Storage

Store leftover soup in an airtight container in the refrigerator for up to 3 days. Reheat gently on the stovetop over low heat, stirring occasionally to prevent scorching. This soup can also be frozen for up to 2 months; thaw overnight in the fridge before reheating.

How to Serve

A white bowl filled with smooth, creamy beige soup, topped with small green herb pieces and a sprinkle of ground black pepper; a silver spoon with soup inside is held by a woman's hand just above the bowl. The bowl sits on a white plate with a cracked pattern, placed on a beige cloth over a white marbled surface. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use regular white onions instead of sweet onions?

Yes, you can, but sweet onions provide a milder, sweeter flavor that balances the soup. If you use regular onions, consider adding a pinch of sugar to help with caramelization.

Why do I need to roast the garlic whole and in the skin?

Roasting garlic whole and unpeeled softens the cloves, mellows their flavor, and brings out natural sweetness without burning or bitterness, making it perfect for blending into the soup.