Roasted Garlic Onion Soup (Print Version)

Slow-roasted garlic and caramelized onions blend with crispy herb croutons in a rich, comforting soup.

# What You’ll Need:

→ Vegetables

01 - 3 large yellow onions, thinly sliced
02 - 2 whole heads garlic
03 - 1 large leek, white and light green parts, sliced
04 - 1 celery stalk, diced
05 - 1 medium carrot, diced

→ Fats & Oils

06 - 4 tablespoons olive oil, divided
07 - 2 tablespoons unsalted butter

→ Liquids

08 - 1/2 cup dry white wine
09 - 5 cups vegetable broth
10 - 1 teaspoon soy sauce, optional

→ Herbs & Seasonings

11 - 2 sprigs fresh thyme
12 - 1 bay leaf
13 - 1/2 teaspoon dried oregano
14 - Salt and black pepper to taste

→ Herb Croutons

15 - 3 cups day-old baguette, cut into 3/4-inch cubes
16 - 2 tablespoons olive oil
17 - 1 tablespoon fresh parsley, chopped
18 - 1 teaspoon dried thyme or Italian herbs
19 - 1/4 teaspoon garlic powder
20 - Pinch of salt

# How to Make It:

01 - Preheat oven to 400°F. Slice tops off garlic heads, drizzle each with 1/2 tablespoon olive oil, wrap in foil, and roast for 40 minutes until soft and golden. Cool slightly, then squeeze roasted garlic from skins and set aside.
02 - While garlic roasts, heat 1 tablespoon olive oil and butter in large pot over medium-low heat. Add onions, leek, celery, and carrot. Cook, stirring frequently, until onions are deeply caramelized and golden brown, approximately 25 to 30 minutes.
03 - Pour white wine into pot, scraping up browned bits from bottom. Simmer until liquid is reduced by half.
04 - Stir in roasted garlic, vegetable broth, soy sauce if using, thyme sprigs, bay leaf, and oregano. Bring to boil, then reduce heat and simmer uncovered for 25 minutes. Remove thyme sprigs and bay leaf.
05 - Toss bread cubes with 2 tablespoons olive oil, parsley, dried thyme, garlic powder, and salt. Spread on baking sheet and bake at 400°F for 10 to 12 minutes, turning once, until golden and crisp.
06 - Taste soup and adjust seasoning with salt and pepper. For smoother texture, blend part or all of soup with immersion blender.
07 - Ladle soup into bowls and top with generous handful of herb croutons. Garnish with fresh parsley if desired.

# Additional Tips::

01 -
  • The roasted garlic becomes almost creamy and sweet, nothing like raw garlic's sharp bite, making even skeptics ask for seconds.
  • Those crispy herb croutons transform from a side thought into the moment people actually fight over the last spoonful.
  • It feels fancy enough for company but honest enough for a solitary evening when you need something real.
02 -
  • Don't skip the slow caramelization of onions—rushing this step by cooking on higher heat gives you cooked onions, not the sweet, deep caramelized ones that make this soup special.
  • If your roasted garlic cloves seem stubborn about coming out of their skins, let them cool a bit longer or run them under warm water; patience here prevents frustration.
03 -
  • Make the croutons while the soup simmers so they're still warm and crispy when you serve—they get soggy fast, so timing matters.
  • Save a little broth after blending if you go that route, so you can loosen the soup to your preferred consistency right before serving.
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