Save on Pinterest

Slow-Cooked French Onion Soup

Total Time

Prep: 30 min. Cook: 7 hours


8 servings (2 quarts)

My husband and I love French onion soup, so I wondered if I could turn it into a less labor-intensive dish by altering my recipe to work in a slow cooker. The rich, cheesy result was an instant winner at home. —Ronda Eagle, Goose Creek, South Carolina
Slow-Cooked French Onion Soup Recipe photo by Taste of Home
Every editorial product is independently selected, though we may be compensated or receive an affiliate commission if you buy something through our links. Ratings and prices are accurate and items are in stock as of time of publication.


  • 2 tablespoons butter, cubed
  • 2 large sweet onions, halved and thinly sliced
  • 1 large red onion, halved and thinly sliced
  • 1/2 teaspoon coarsely ground pepper
  • 2 cans (10-1/2 ounces each) condensed beef broth, undiluted
  • 3 cups water
  • 3/4 cup white wine or regular-strength beef broth
  • 2 fresh thyme sprigs
  • 1 fresh parsley sprig, optional
  • 1 bay leaf
  • 2 teaspoons Worcestershire sauce
  • 16 slices French bread (1/4 inch thick)
  • 3/4 cup shredded Gruyere or Swiss cheese


  1. Place butter in a 5-qt. slow cooker. Top with sweet and red onions; sprinkle with pepper. Cook, covered, on low until onions are tender, 5-6 hours.
  2. Stir in broth, water, wine, herbs and Worcestershire sauce. Cook, covered, on low until flavors are blended, 2-3 hours. Remove herb sprigs and bay leaf.
  3. To serve, preheat broiler. Place bread on a baking sheet; broil 4 in. from heat until lightly toasted, 1-2 minutes per side. Top bread with cheese; broil until cheese is melted, 1-2 minutes. Divide soup among eight bowls; top with cheese toasts and serve immediately.

Test Kitchen tips
  • Gruyere cheese is delicious in this recipe—its sweet, nutty flavor goes well with the oniony broth, and it melts wonderfully.
  • Toasting the bread with cheese separately, instead of broiling on top of the soup in crocks, prevents the underside of the bread from becoming soggy.
  • Nutrition Facts

    1 serving: 157 calories, 7g fat (4g saturated fat), 19mg cholesterol, 706mg sodium, 15g carbohydrate (6g sugars, 1g fiber), 7g protein.

    Recommended Video