Slow-Cooker French Onion Soup

Slow-Cooker French Onion Soup

3 Reviews
From: EatingWell Magazine, Soup Cookbook

In this genius slow-cooker soup recipe, two types of onions are caramelized for hours before adding a sherry-spiked broth. For a bistro-worthy presentation, ladle the soup into ovenproof crocks, top with the bread and cheese and broil.

Ingredients 8 servings

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Original recipe yields 8 servings
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  • Soup
  • 2 tablespoons butter, cut into 8 pieces
  • 2 tablespoons extra-virgin olive oil
  • 8 sprigs fresh thyme
  • 4 cloves garlic, smashed
  • 1 bay leaf
  • 2 pounds yellow onions, halved and sliced (see Tip)
  • 2 pounds red onions, halved and sliced
  • 1 teaspoon salt
  • ¾ teaspoon ground pepper
  • 4 cups low-sodium beef broth
  • ¼ cup dry sherry
  • Cheese Toasts
  • 8 diagonal slices baguette ( ½-inch-thick), toasted
  • 1 cup shredded Gruyère or Swiss cheese


  • Active

  • Ready In

  1. To prepare soup: Scatter butter in a 6- to 7-quart slow cooker (see Tip). Add oil, thyme, garlic and bay leaf, then onions. Sprinkle with salt and pepper. Cover and cook on High for 8 hours.
  2. Bring broth and sherry to a boil in a saucepan. Remove the thyme sprigs and bay leaf from the slow cooker. Pour in the broth and cook on High, uncovered, for 10 minutes.
  3. To prepare cheese toasts: Meanwhile, position rack in upper third of oven; preheat broiler to high. Top each baguette slice with 2 tablespoons cheese. Broil until the cheese is melted, 1 to 2 minutes. Divide the soup among 8 bowls. Top each with a cheese toast.
  • Tips: Take the tears out of onion prep: Refrigerate whole, unpeeled onions for about 30 minutes before slicing or chopping. The cold “chills out” the sulfur compounds that can irritate your eyes and make you cry.
  • For easy cleanup, try a slow-cooker liner. These heat-resistant, disposable liners fit neatly inside the insert and help prevent food from sticking to the bottom and sides of your slow cooker.
  • To make ahead: Refrigerate soup (Steps 1-2) for up to 5 days or freeze for up to 3 months. Make cheese toasts before serving.
  • Equipment: 6- to 7-quart slow cooker

Nutrition information

  • Serving size: 1 cup soup & 1 cheese toast
  • Per serving: 271 calories; 12 g fat(5 g sat); 5 g fiber; 31 g carbohydrates; 12 g protein; 40 mcg folate; 22 mg cholesterol; 9 g sugars; 222 IU vitamin A; 16 mg vitamin C; 194 mg calcium; 1 mg iron; 529 mg sodium; 428 mg potassium
  • Nutrition Bonus: Vitamin C (27% daily value)
  • Carbohydrate Servings: 2
  • Exchanges: 4 vegetable, 1½ fat, ½ high-fat protein, ½ starch

Reviews 3

January 25, 2018
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By: I love Lemons
Really good! I would suggest adding at least two more cups of broth than the recipe suggested.
September 27, 2016
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By: EatingWell User
Bland and not enough broth.
March 09, 2016
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By: EatingWell User
Great recipe & easy to make! I made this for lunch, so I cooked the onions overnight. I've read on other sites, that people cooked the onions in their garage. Your house will definitely smell like onions. I also added 8 cups beef broth, 4 was definitely not enough, and 1/2 cup sherry. I also added 2 tsp. balsamic vinegar. I brought it to work to share and everyone loved it. Definitely a keeper!! Pros: so easy in the slow cooker, great tasting Cons: not enough broth
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