Slow-cooker French onion soup

Prep 30 min
Total 7 hours 30 min
Serves 4



1.75 kg
cooking onions, thinly sliced (about 14 cups)
3 tbsp
butter, cubed
1/4 tsp
4 1/2 tsp
all-purpose flour
3 tbsp
vermouth, or dry white wine
900-mL carton
1/3 cup
1 tbsp
butter, at room temperature
2 cups
grated gruyere or emmental cheese


  • COMBINE onions with butter and salt in slow cooker insert. Season with fresh pepper. Cover and cook on high until onions are soft and dark brown, about 6 hours.
  • STIR in flour until well combined. Stir in vermouth. Scrape up brown bits from bottom. Add broth and water. Cover and continue cooking on high for 1 1/2 hours.
  • POSITION rack in top third of oven. Preheat broiler. Cut bread into 8 slices, each 1/2 in. thick. Butter both sides and place on a baking sheet. Broil until lightly golden, about 1 min per side.
  • ARRANGE 4 oven-safe soup bowls on a baking sheet. Ladle soup into bowls. Top each with 2 toasts. Sprinkle with cheese. Broil until cheese is bubbly, 2 to 4 min.
  • Make-ahead tip: Soup (without toasts) keeps well up to 3 days in the fridge or up to 2 months in the freezer. Flavour will improve as it sits.

Note: Our slow cooker recipes are developed with a 7 quart slow cooker.


Calories 587, Protein 26 g, Carbohydrates 56 g, Fat 30 g, Fibre 7 g, Sodium 1840 mg. Excellent source of Vitamin B6

Chatelaine Quickies: French onion macaroni and cheese

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