Slow Cooker French Onion Soup

A rich and flavorful slow cooker French onion soup, perfect for chilly evenings and gatherings.

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Prep Time 15

Cook Time 6

Total Time 6 15

Servings: 6 bowls

Course: Soup

Cuisine: French

Calories: 350

4 large Onions Sweet onions like Vidalia or yellow onions for best flavor.
4 tablespoons Unsalted butter Adds richness and helps caramelize the onions.
1 tablespoon Olive oil Prevents butter from burning.
1 teaspoon Sugar Helps to caramelize the onions.
4 cloves Garlic Minced for added aroma and depth.
8 cups Beef or vegetable broth High-quality broth for a rich base.
1 cup Dry white wine Adds acidity and complexity; can substitute with more broth.
2 teaspoons Fresh thyme leaves Fresh herbs elevate the flavor.
to taste Salt Season to taste.
to taste Pepper Season to taste.
1 baguette Baguette Sliced for toasting, serves as a crunchy topping.
2 cups Shredded Gruyère cheese Melts beautifully and adds a creamy, nutty flavor.

Peel and slice the onions thinly. Aim for even slices for uniform cooking.
In a large skillet, melt the unsalted butter and olive oil over medium heat. Add the sliced onions and sugar, stirring to coat. Cook for about 15-20 minutes until golden brown.
Add minced garlic to the skillet and cook for an additional 1-2 minutes until fragrant.
Transfer the caramelized onions and garlic to the slow cooker. Pour in the broth and dry white wine. Add thyme, salt, and pepper, stirring to combine.
Cover and cook on low for 6-8 hours or on high for 3-4 hours.
About 30 minutes before serving, preheat the oven to 400°F (200°C). Slice the baguette and toast in the oven for 5-7 minutes until golden brown.
Ladle the soup into oven-safe bowls, top with toasted baguette slices, and sprinkle with shredded Gruyère cheese.
Place the bowls under the broiler for 2-3 minutes until the cheese is bubbly and golden. Serve hot.

This slow cooker French onion soup is a comforting dish perfect for chilly evenings and gatherings.