Irresistible Low-Fat Roasted Onion Garlic Soup Recipe

I often make this Low-Fat Roasted Onion Garlic Soup when I need deep, savory comfort without the heaviness of cream-based bowls.

You might think achieving rich flavor requires butter, but roasting the aromatics first does all the heavy lifting. This simple method transforms humble ingredients into a sweet, golden broth that feels like a warm hug.

The Secret to Perfect Low-Fat Roasted Onion Garlic Soup

The magic here lies in the slow-roasting process which draws out natural sugars from the garlic and shallots. You get an intense depth of flavor that usually takes hours of stovetop stirring to achieve.

It is also incredibly versatile, fitting perfectly into a light lunch rotation or serving as an elegant starter for dinner. I love how the house smells while the vegetables soften and brown in the oven.

Clean-up is surprisingly minimal since most of the work happens on a single roasting pan before moving to the pot. You get maximum taste with very little active effort, which is my favorite way to cook.

If this dish hit the spot, you’ll want to try my Savory Herb Brown Butter Scallops Recipe next, plus the Quick Muhammara Recipe delivers the same bold flavors. Both recipes share the same simple approach that makes weeknight cooking stress-free.

Gathering Your Low-Fat Roasted Onion Garlic Soup Ingredients

Here are the fresh components you need to build this soup:

• Spanish onions: 3 large ones, cut in half lengthwise and then thinly sliced.
• Chicken broth: 4 cups total, divided for roasting and simmering.
• Garlic: 1 large head, cloves separated, peeled, and cut in half.
• Large shallots: 3 bulbs, peeled and cut in half.
• Olive oil: 2 teaspoons for roasting the vegetables.
• Apple cider vinegar: 1/4 cup (a non-alcoholic substitute for the brandy originally called for).
• Fresh thyme: 1 tablespoon chopped (or 1 teaspoon dried thyme leaves).
• Parmesan cheese: 1/4 cup freshly grated for serving.
• Salt and pepper: To taste for seasoning the final broth.

Step-by-Step Low-Fat Roasted Onion Garlic Soup Instructions

Let’s get the oven going and start roasting these vegetables.

1. Begin by setting your oven rack to the lowest possible position and preheating the oven to 450 degrees Fahrenheit. While the oven heats up, prepare a large, shallow roasting pan by combining your sliced onions, halved shallots, garlic cloves, and olive oil, tossing them well to coat evenly.
2. Place the pan in the oven and roast the mixture for 25 to 35 minutes, making sure to open the oven and stir the vegetables every 5 minutes. You are looking for the onions to turn a deep, rich golden brown without burning, as this caramelization is the foundation of the Low-Fat Roasted Onion Garlic Soup flavor.
3. Once the vegetables are beautifully roasted, carefully remove the pan from the oven and pour in 1 cup of the chicken broth immediately. Stir the liquid vigorously against the bottom of the pan to scrape up and dissolve all the dark, caramelized bits, which is where the most concentrated flavor hides.
4. Transfer the entire onion mixture and the liquid from the roasting pan into a large soup pot. Add the apple cider vinegar (or extra broth if you prefer), the chopped thyme, and the remaining 3 cups of chicken broth to the pot.
5. Bring the soup to a boil over medium-high heat, then immediately reduce the heat to low and cover the pot with a lid. Let it simmer gently for about 30 minutes to allow the roasted garlic and onions to fully meld with the broth.
6. After simmering, taste the broth and season it with salt and pepper according to your preference. Ladle the hot soup into bowls and serve it topped with the freshly grated Parmesan cheese and perhaps a slice of toasted bread.

My Best Tips for Perfect Low-Fat Roasted Onion Garlic Soup

Don’t rush the roasting phase, as those browned bits on the pan are essential for the final broth color. I always let the onions get deep golden brown to ensure the Low-Fat Roasted Onion Garlic Soup has a robust taste.

If you prefer a smoother texture, feel free to use an immersion blender to puree half of the soup before serving. This trick adds body and creaminess without needing any dairy or heavy thickeners.

Taste your broth carefully at the end before adding salt, as the reduction process concentrates the natural sodium. I find that a final splash of vinegar brightens the Low-Fat Roasted Onion Garlic Soup perfectly just before serving.

How I Like to Serve This Low-Fat Roasted Onion Garlic Soup

A slice of crusty sourdough bread is non-negotiable for soaking up every drop of the savory broth. You can also float a cheesy toast on top for a lighter take on the classic French bistro style.

I sometimes pair this with a crisp green salad to keep the meal feeling fresh and balanced. It makes for a wonderful light supper that leaves you feeling satisfied but not weighed down.

I love seeing what you create in your kitchen, so please tag me if you make this recipe and follow along on Pinterest.

Low-Fat Roasted Onion Garlic Soup

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• Author: Amelia Bryan
• Total Time: 1 hr 20 min
• Yield: 4 servings
• Diet: Low-Fat

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Description

A savory, comforting soup made by roasting onions, garlic, and shallots to caramelized perfection. This low-fat recipe offers deep flavor without heavy cream.

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Ingredients

• 1 head garlic, cloves separated, peeled and cut in half
• 2 teaspoons olive oil
• 3 large shallots, cut in half
• 3 Spanish onions, cut in 1/2 lengthwise then thinly sliced
• 1/4 cup apple cider vinegar (or vegetable broth)
• 4 cups chicken broth
• 1/4 cup parmesan cheese, freshly grated
• 1 tablespoon fresh thyme, chopped (or 1 tsp dried)

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Instructions

1. Preheat the oven to 450 degrees F and set the rack to the lowest position.
2. Combine onions, shallots, garlic, and olive oil in a large shallow roasting pan, tossing to coat.
3. Roast for 25 to 35 minutes, stirring every 5 minutes until vegetables are golden brown.
4. Remove from oven, add 1 cup of chicken broth to the pan, and scrape the bottom to dissolve caramelized bits.
5. Transfer the mixture to a soup pot and add the apple cider vinegar, thyme, and remaining broth.
6. Bring to a boil, reduce heat to low, cover, and simmer for 30 minutes.
7. Season with salt and pepper to taste.
8. Serve hot, garnished with grated Parmesan cheese.

Notes

This recipe traditionally uses brandy, but I have substituted apple cider vinegar for a non-alcoholic alternative. You can also use white grape juice or additional broth.

• Prep Time: 15 min
• Simmering: 30 min
• Cook Time: 1 hr 5 min
• Category: Dinner
• Method: Roasting
• Cuisine: French-inspired

Nutrition

• Serving Size: 1 bowl
• Calories: 180
• Sugar: 8g
• Sodium: 850mg
• Fat: 4g
• Saturated Fat: 1g
• Unsaturated Fat: 2g
• Trans Fat: 0g
• Carbohydrates: 22g
• Fiber: 3g
• Protein: 9g
• Cholesterol: 5mg

Keywords: Low-Fat Roasted Onion Garlic Soup, healthy onion soup, roasted garlic soup, dairy free soup, easy dinner recipe