This French Crockpot Onion Soup is an easy and delicious home cooking option. It can be served as a light soup or topped with bread and cheese for a heartier, more traditional option! Either way is delicious!
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Best French Onion Soup Recipe
There’s nothing quite like sitting down with a cozy bowl of warm French Onion Soup. And this Crockpot French Onion Soup is the perfect recipe for it! It’s a rich, flavorful soup that can be served as is or topped with toasted bread and gooey, golden cheese. I mean, what sounds cozier than that?
The other benefit? It’s so easy to whip. Just throw a few basic ingredients into the crockpot and let it work its magic. This recipe yields a ton and, while slow cooking, takes very little time to prep. Only 15 minutes of training required.
What is the Difference Between Onion Soup and French Onion Soup?
Although the two are similar, there are a few subtle differences.
First, French onion soup typically uses a combination of yellow and red onions to create a specific flavor profile. English onion soup uses an even wider variety of onions, including shallots and leeks.
Second, the broth. French onion soup is always made with beef broth. English onion soup, on the other hand, can be made with any type of broth.
And finally, the toppings! Both onion soups are traditionally topped with bread and cheese. However, French onion soup is usually served with cheeses such as Gruyere and mozzarella. English onion soup is traditionally served with cheddar.
ingredients required
- onions: We like to use both yellow and red for a nice compliment of flavors.
- Garlic: Use freshly chopped garlic for the best flavor.
- coconut sugar: This adds a natural sweetness to the soup and enhances the sweetness of the onions.
- Butter, Oil and Balsamic Vinegar: These give us the liquid mixture to slowly cook the onions. They add flavor and texture, and the vinegar helps tenderize the onions.
- Broth: Beef broth provides a flavorful base for the soup.
- fish sauce: Gives the soup a touch of hearty umami flavor.
- Spices: We use a combination of fresh and dried thyme, bay leaves, black pepper and salt to enhance the flavor of the soup.
- Arrowroot Flour: Helps thicken the soup.
Optional toppings
- Cheese: You can’t go wrong with a topping of melted Gruyere and mozzarella.
- Bread: A portion of bread with soup is never a bad idea. They can be either homemade or store-bought to use for toasting and garnishing the soup before baking. Use gluten free or regular as needed.
- Red Pepper Flakes: These are also optional, but if you love a little extra spice, a sprinkling of pepper flakes will do the trick!
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How to make French Crockpot Onion Soup
This really is the best French onion soup. This hearty recipe only takes 15 minutes to prep and then the cooking is done!
- Cooking onions: Place the butter and oil in the bottom of the slow cooker, then add the onions, coconut sugar, garlic, vinegar, thyme, bay leaves, and half the salt and pepper. Cover and cook on low for 6 hours.
- Add broth: Next, add the beef broth, fish sauce, arrowroot flour, and remaining salt and pepper. Cover and cook for another 2 hours.
- Bake: You’re almost there! Once the soup is slow-cooked, you can serve it entirely as is. BUT if you want to serve it more traditionally, divide into ovenproof bowls and top each bowl with a slice of toasted bread. Sprinkle with cheese, then bake at 350ºF for 20-30 minutes. Finally, grill on high for 1 minute to brown the cheese.
- Cool and serve: Remember that the shells will be hot when you remove them from the oven. Let them cool for a few minutes before reaching into the soup.
Which onions are best for french onion soup?
This French Onion Soup recipe uses two types of onions. First, we use yellow onions, which have a sweeter, lighter flavor. Second, we use red onions, which have more depth of flavor and a hint of bitterness.
The two together make a deliciously nuanced and flavorful French Onion Soup!
Can you put raw onions in the slow cooker?
Yes! Except that you let them cook on their own first. In a traditional stovetop French onion soup recipe, the onions are first cooked individually to give them time to really caramelize.
For the crockpot version we add them raw to the crockpot but cook them on their own for 6 hours with just the garlic, sugar, butter, oil and vinegar. This helps to really bring out their sweetness and flavor. Once well cooked, add the rest of the soup ingredients.
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How do you deepen the flavor of French onion soup?
This French Onion Soup recipe is plenty deep, rich, and flavorful on its own. The addition of balsamic vinegar, fish sauce and spices gives it a lot of depth of flavor.
However, some people like to add a splash of red wine or even some Worcestershire sauce to add another layer of flavor. Feel free to do that if you like!
Is French Onion Soup Healthy?
Good news! While this French Onion Soup looks and tastes like total comfort food, it’s actually a healthy meal. Onion
Good news! Sure, it’s comfort food, but French onion soup is actually a healthy meal. Onions are rich in antioxidants and packed with nutrients. What could be better than guilt-free comfort food?
tips and hints
- Use ovenproof bowls. We don’t want them to crack while baking!
- Want to make your French Onion Soup in the Instant Pot? It’s a little more convenient than the crockpot version, but perfect if you’re short on time. For full instructions see the notes on the recipe card below.
- For a lightened option, Just follow the recipe as is but leave the toppings/baking in the oven. Your soup will still be delicious!
serving suggestions
French onion soup is a delicious meal on its own, but it can be fun to round out with a few side dishes. Here are a few favourites:
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How to save
I recommend saving leftovers without the bread and cheese, so only bake as many bowls as you will serve.
Leftover soup will keep in an airtight container in the fridge for 3-4 days or in the freezer up to 3 months.
To reheat, heat on stovetop on low until heated through, then portion into bowls, spread bread and cheese on top and bake as directed.
More slow cooker recipes
Watch the video:
Casserole French Onion Soup
This French Crockpot Onion Soup is delicious and comforting. Serve as a light soup or serve with bread and cheese for a heartier option!
- Preparation time: 15 minutes
- Cooking time: 8 hours and 30 minutes
- Total time: 8 hours and 45 minutes
- Yield: 4–6 1x
- 3 tablespoons butter
- 1 tablespoon extra virgin olive oil or avocado oil
- 4 white onions, sliced
- 2 red onions, sliced
- 1 tablespoon coconut sugar
- 3 Garlic cloves, chopped
- 1 teaspoon salt, more to taste
- 1 teaspoon black pepper, more to taste
- 1/4 cup balsamic vinegar
- 2 teaspoons dried thyme or 2 fresh sprigs of thyme
- 2 bay leaves
- 7 cups beef broth
- 1/2 teaspoon fish sauce
- 1 tablespoon arrowroot flour
- Optional: red pepper flakes for serving
- Options: 1/4 cup grated Gruyere cheese
- Optional: 1/4 cup grated mozzarella cheese
- Optional: 1 serving of bread (see recipe here or here for nut-free)
- Put butter and oil in the bottom of your slow cooker insert.
- Add chopped onions, coconut sugar, garlic, balsamic vinegar, half the salt and pepper, thyme and bay leaves. Flip to coat and cook on low for 6 hours.
- After 6 hours, add beef broth, fish sauce, arrowroot flour, and the remaining salt and pepper.
- Cook for the remaining 2 hours. Remove bay leaves and sprigs of thyme if using fresh thyme. Taste and add salt and pepper to taste.
- Preheat the oven to 350°F. Divide the soup among ovenproof bowls. Place a slice (or two) of toasted bread on top of each and sprinkle cheese in a thick layer over the bread to the rim of the bowl. Bake for 20 to 30 minutes until cheese starts to bubble. Grill on high for 1 minute.
Remarks
Preparation in the Instant Pot:
Press the fry function on the Instant Pot. Add the butter and oil to the saucepan along with the onions. Cook for 5 minutes, stirring once. Add coconut sugar, garlic, balsamic vinegar, salt and pepper, thyme and bay leaves and cook on high pressure for 20 minutes. When you’re done, use the quick release feature
Press Cancel and remove the lid. When there is a lot of liquid at the bottom of the pot, press fry and cook until almost evaporated and the onions are a nice brown color and very jammy.
Add the arrowroot and stir until gone. AAdd 4 cups of beef broth (this is different than the slow cooker instructions) and fish sauce and close the lid and set on seal. Finish cooking with manual high pressure for 5 minutes. Use the quick release feature. Season to taste. If you are topping the soup with bread and cheese, follow the instructions above from step 5.
nutrition
- Serving size: 4-6
- Calories: 163
- Sugar: 6 g
- Sodium: 981mg
- Fat: 10g
- Saturated Fatty Acids: 4.6g
- Carbohydrates: 11.1g
- Fiber: 1.8g
- Protein: 7.1g
- Cholesterol: 16mg