Slow Cooker Gluten-Free French Onion Soup

My favourite homemade French onion soup recipe that’s easy to make and full of the richest caramelized onion flavours.

This Slow Cooker Gluten-Free French Onion Soup is a hearty and comforting dish that’s perfect for cozy nights in. What makes this recipe stand out is the rich depth of flavour that develops over time in the slow cooker. The combination of caramelized onions, savory broth, and a hint of sweetness creates a beautiful balance of flavours that will warm you up from the inside out.

Traditionally, French onion soup is topped with a crusty baguette and melted cheese, but for this gluten-free version, I’ve swapped the baguette for a thick slice of gluten-free sourdough bread. The sourdough offers a slight tangy flavour that pairs beautifully with the caramelized onions and cheese, elevating the soup to new levels of deliciousness. Simply place the toasted gluten-free sourdough on top of the soup, cover with cheese, and let it melt into the broth for a truly indulgent experience.

The first step to making traditional French onion soup is to transform that big pile of raw onions into the decadent, sweet, and irresistibly caramelized onions. This will form the rich base of this recipe. Caramelization is actually a really simple process, but it does take some time. So turn some music on. Maybe pour yourself a glass of that wine we will be using, and get ready to spend some quality time by the stove as we work some onion magic.

Tips for Perfectly Caramelized Onions:

1. Use a large pan: Caramelizing onions requires space for them to cook evenly. If the pan is overcrowded, the onions will steam instead of caramelize.
2. Cook on low heat: Patience is key when caramelizing onions. Cooking them on low heat allows them to break down slowly, bringing out their natural sweetness.
3. Stir regularly: Stir the onions every 5 minutes or so to prevent them from sticking to the pan and burning. This also ensures they cook evenly.
4. Don’t rush it: If you try to speed up the process by turning up the heat, the onions will burn before they caramelize properly. Slow and steady wins the race!
5. Deglaze with wine: Once your onions are caramelized, deglaze the pan with a splash white wine to loosen any flavourful bits stuck to the pan. This step adds extra richness to the soup.

Storage Tips for Slow Cooker Gluten-Free French Onion Soup

This Slow Cooker Gluten-Free French Onion Soup is not only a delicious meal, but it also stores incredibly well, making it perfect for meal prep or leftovers. Here are some tips to ensure your soup stays fresh:

1. Refrigeration:
   • Once your soup has cooled to room temperature, transfer it into an airtight container and store it in the refrigerator. It will keep for up to 3-4 days.
   • If you have leftover sourdough bread and cheese on top, it’s best to remove it before storing, as the bread can become soggy. You can always add fresh bread and cheese when reheating.
2. Freezing:
   • This soup freezes wonderfully for up to 3 months. After cooling, transfer the soup into freezer-safe containers or heavy-duty freezer bags. For the best results, store the soup without the bread and cheese, as these can lose their texture when frozen.
   • To freeze in portions, divide the soup into smaller containers or bags so you can easily reheat just the amount you need.
   • When ready to reheat, defrost in the refrigerator overnight or use the defrost setting on your microwave. Once thawed, reheat on the stove or in the microwave until it reaches a piping-hot temperature.
3. Reheating:
   • To reheat, simply place the soup in a pot over medium heat, stirring occasionally, until it’s heated through. You can also microwave individual portions, covered with a microwave-safe lid, in short bursts, stirring in between.
   • If you removed the bread and cheese before storing, you can top the soup with fresh gluten-free sourdough bread and cheese, and grill/broil it in the oven for a few minutes to melt the cheese and get the bread toasted.

With these storage tips, you can enjoy this comforting soup over multiple meals, saving time while still indulging in the delicious flavours of your homemade French onion soup!

This recipe is perfect for meal prepping as it can be easily made ahead of time in your slow cooker. The slow cooking method allows the flavours to meld together, making each bite even more satisfying. Whether you’re serving it as a main dish or as an appetizer for a gathering, this gluten-free French onion soup will become a go-to recipe in your kitchen. Plus, it’s an easy way to enjoy a classic French onion soup while accommodating your dietary preferences.

Slow Cooker Gluten-Free French Onion Soup

Enjoy the rich, comforting flavors of this classic French onion soup, made completely gluten-free. Slow-cooked caramelized onions simmered in a savory broth, topped with a crispy gluten-free baguette and melted cheese for the perfect cozy dish.

Cooking Method: Slowcooker Cuisine: French Courses: Appetizers, Dinner, Lunch, Slowcooker Recipe Keys: A appetizer D Dinner L lunch S Slowcooker

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Pin Recipe appetizer

Prep Time 15 mins Cook Time 6 hrs Total Time 6 hrs 15 mins Dietary:

G Gluten Free

Ingredients

Servings

• 4 large yellow onions (peeled and thinly sliced)

• 3 tbsp butter

• 4 cloves garlic (finely chopped or minced)

• 118 ml white wine

• 1182 ml beef broth (or 4 beef stock cubes in 1182ml water)

• 1 bay leaf

• 1 tsp dried thyme

• salt and freshly-cracked black pepper, to taste

• 4-6 slices Gluten free Sourdough Bread

• grated or sliced cheese (such as Gruyere, Asiago, Swiss, Gouda or Mozzarella)

Instructions

1. In a large pot, melt the butter over medium heat. When it begins to foam, add the onions and stir to coat them in butter.
2. Reduce the heat to medium-low and cook for about 30 minutes, stirring occasionally, until the onions soften and turn semi-transparent.
3. Increase the heat to medium-high, add your garlic and a pinch of salt, and cook for an additional 20–30 minutes, stirring more frequently, until the onions are deep golden and caramelized.
4. Deglaze the pot by adding the wine and simmering for 2 minutes, scraping up any bits stuck to the bottom until most of the liquid has evaporated..
5. Add the onions, broth/stock, thyme, and bay leaves to your slow cooker, stir well.
6. Cook on high for 4-6 hours.
7. Taste and season with salt and pepper. Ladle the soup into bowls.

8. Lightly toast both sides of the sourdough bread slices until golden.

9. Top each bowl of soup with the toasted bread and top with cheese and grill until melted and bubbly with brown spots.
10. Garnish with fresh parsley or thyme if desired, and serve.