Slow Cooker French Onion Soup

Course: Soup

Cuisine: French

Diet: Vegetarian

Prep Time: 15

Cook Time: 10

Slow Cooker Time: 5

Total Time: 5 25

Servings: servings

Calories: 388kcal

Author: Shruthi Baskaran-Makanju

This slow cooker French onion soup is like a cozy hug in a bowl. With caramelized onions, gooey cheese, and a hint of thyme, it's made entirely in the slow cooker! So worth it!

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Equipment

1 Slow cooker

Ingredients

4 yellow onions thinly sliced
2 tablespoons butter or olive oil for a vegan option
4 cloves garlic minced
1 tablespoon sugar
1 tablespoon balsamic vinegar
2 tablespoon dry sherry optional
8 cups vegetable broth low-sodium
2 sprigs fresh thyme substitute, 1 tsp dried thyme
2 bay leaves
½ teaspoon salt
¼ teaspoon black pepper adjust to taste
1 tablespoon soy sauce or tamari for gluten-free
1 baguette sliced
2 cups Gruyère cheese freshly shredded

Instructions

Set your slow cooker to high. Add melted butter (or olive oil), sliced onions, and sugar (if using). Stir to coat the onions evenly. Prop the lid open slightly to allow steam to escape and cook for 6-8 hours on low, stirring occasionally, until onions are golden brown and soft.
Once onions are caramelized, add minced garlic and cook for another 2-3 minutes on low, stirring occasionally.
Add balsamic vinegar and sherry to deglaze the slow cooker. Stir well to pick up any browned bits.
Add vegetable broth, thyme, bay leaves, soy sauce, salt, and pepper. Stir, cover, and cook on low for another 4-6 hours.
Preheat the oven to 400°F (200°C). Slice the baguette and toast until golden and crispy.
Remove thyme sprigs and bay leaves from the soup. Ladle the soup into oven-safe bowls, top with toasted baguette slices, and sprinkle with shredded Gruyère.
Place the bowls under the broiler for a few minutes until the cheese melts and is bubbly.
Serve with extra thyme or a drizzle of balsamic reduction if desired.

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