• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
Hint of Healthy
  • Recipes
    • All Recipes
    • Air Fryer
    • Instant Pot
    • Slow Cooker
    • Collections
  • Cooking Skills
  • About
  • Subscribe
menu icon
go to homepage
  • All Recipes
  • Air Fryer
  • Instant Pot
  • Slow Cooker
  • Subscribe
  • About
    • Facebook
    • Instagram
    • Pinterest
  • subscribe
    search icon
    Homepage link
    • All Recipes
    • Air Fryer
    • Instant Pot
    • Slow Cooker
    • Subscribe
    • About
    • Facebook
    • Instagram
    • Pinterest
  • ×

    Home » Slow Cooker Soups

    Slow Cooker French Onion Soup

    Posted: Apr 3, 2020 · Updated: Sep 9, 2020 by Tonje

    189 shares
    Jump to Recipe

    This hearty and delicious slow cooker French onion soup is a classic, comforting dish. The onions are caramelized beautifully, and give the soup a really unique flavor.

    French onio soup in a bowl.

    Jump to:
    • 🥘 Ingredients
    • 🔪 Instructions
    • 🧅 Onions
    • 💭 Top tips
    • 🥗 Serving suggestions
    • 🍲 Leftovers
    • 🍴 You might also like these recipes..
    • 📋 Frequently asked questions
    • Recipe

    This post may contain affiliate links. Read more about it in the privacy policy.

    French onion soup is a family favorite all over the world. Preparing it in your slow cooker will give the onions a chance to really enhance their flavor, with little to no effort required.

    If you love this recipe, you might also want to check out my Slow Cooker Leek and Potato Soup!

    🥘 Ingredients

    French onion soup requires a lot of fresh onions, butter, bay leaves, vegetable or beef stock as well as salt and pepper.

    The French onion soup is a beautiful classic soup where the flavors of the vegetable stock and caramelized onions are in focus. Other ingredients are not typically used.

    🔪 Instructions

    Peel the onions and slice them thinly. Add them to the slow cooker along with the butter. Place the lid on top, and leave the slow cooker on low for 10-12 hours, or overnight. The onions will caramelize and soften.

    Then, add the stock and bay leaves. Leave the soup to cook for another 7-10 hours.

    Remove the bay leaves and add salt and pepper to taste.

    Add the soup to oven proof bowls. Place a thin slice of bread or a baguette on top, of the soup, and add cheese. Broil the soup in an oven until the cheese has melted. Serve immediately.

    French onion soup being served from a slow cooker.

    🧅 Onions

    French onion soup is typically made with regular yellow or brown onions, however you can also use red onions or a combination of different types of onion.

    I highly recommend slicing the onions thinly and not chopping them. This will give them a nicer texture when you serve it.

    💭 Top tips

    My top advice for how to make the BEST french onion soup:

    • The longer the onions cook, the better they are. This is definitely a recipe you don't want to rush.
    • French onion soup is typically enjoyed as a broth style soup with whole slices of caramelized onions. If you're not too keen on the consistency of soft onions in soup, you can simply use a hand blender to puree the soup smooth.

    🥗 Serving suggestions

    Serve french onion soup with your typical soup side dishes. Extra cheesy bread or baguette is a great option. You can also serve this soup as a light appetizer.

    Onion soup in slow cooker.

    🍲 Leftovers

    Leftover slow cooker french onion soup can be stored in the fridge for up to 3 days, or frozen for up to 6 months. This recipe is perfect as a freezer meal for future dinners.

    If you have leftovers, I highly recommend storing the soup without the cheesy bread on top. Otherwise, the bread will get soggy and might dissolve into the soup.

    🍴 You might also like these recipes..

    If you love slow cooker soups, try any of these recipes:

    • Slow Cooker Meatball Stew
    • Slow cooker stuffed pepper soup
    • Slow cooker chicken taco soup
    • Slow cooker lasagna soup

    📋 Frequently asked questions

    Do I have to add any liquid to the onions? - No. The onions will release moisture as they slow cook, and no liquid is required during the caramelization process.

    Is this recipe allergy friendly? - Always consult the nutrition label of the ingredients you use. This recipe is generally egg free, nut free, gluten free and soy free.

    Do you need to add seasoning to onion soup? - This soup has so much flavor from the caramelized onions. Some recipes use herbs or spices like thyme and cumin, but this is strictly not necessary. If you wish, you can experiement with adding additional seasoning.

    Can I make French onion soup without the bread? - Of course! If you don't want to use cheesy bread, you can serve the soup immediately straight from the Crockpot.

    Which cheese should you use in French onion soup? - Gruyere is the traditional choice, but you can really use any cheese that you like.

    Recipe

    onion soup in a slow cooker.

    Slow Cooker French Onion Soup

    This hearty and delicious slow cooker French onion soup is a classic soup you can make in your Crockpot. The onions are caramelized beautifully, and give the soup a unique flavor.
    No ratings yet
    Created by: Tonje
    Print Recipe Pin Recipe Save Saved!
    Prep Time 5 mins
    Cook Time 20 hrs
    Course Dinner, Soup
    Cuisine French
    Servings 4
    Calories 117 kcal

    Equipment

    • Slow Cooker
    Prevent your screen from going dark

    Ingredients
      

    • 1 kg onions
    • 2 tablespoon butter
    • 1 l vegetable stock (or beef stock)
    • 2 bay leaves
    • salt
    • pepper

    Instructions
     

    • Peel the onions and slice them thinly. Add them to the slow cooker along with the butter. Place the lid on top, and leave the slow cooker on low for 10-12 hours, or overnight. The onions will caramelize and soften.
    • Then, add the stock and bay leaves. Leave the soup to cook for another 7-10 hours.
    • Remove the bay leaves and add salt and pepper to taste.
    • Add the soup to oven safe bowls. Place a thin slice of bread or a baguette on top, of the soup, and add cheese. Broil the soup in an oven until the cheese has melted. Serve immediately.

    Notes

    Do I have to add any liquid to the onions? – No. The onions will release moisture as they slow cook, and no liquid is required during the caramelization process.
    Is this recipe allergy friendly? – Always consult the nutrition label of the ingredients you use. This recipe is generally egg free, nut free, gluten free and soy free.
    Do you need to add seasoning to onion soup? – This soup has so much flavor from the caramelized onions. Some recipes use herbs or spices like thyme and cumin, but this is strictly not necessary. If you wish, you can experiement with adding additional seasoning.
    Can I make French onion soup without the bread? – Of course! If you don’t want to use cheesy bread, you can serve the soup immediately straight from the Crockpot.
    Which cheese should you use in French onion soup? - Gruyere is the traditional choice, but you can really use any cheese that you like.

    Leftovers

    Leftover slow cooker french onion soup can be stored in the fridge for up to 3 days, or frozen for up to 6 months. This recipe is perfect as a freezer meal for future dinners.
    If you have leftovers, I highly recommend storing the soup without the cheesy bread on top. Otherwise, the bread will get soggy and might dissolve into the soup.

    Top tips

    My top advice for how to make the BEST french onion soup:
    • The longer the onions cook, the better they are. This is definitely a recipe you don’t want to rush.
    • French onion soup is typically enjoyed as a broth style soup with whole slices of caramelized onions. If you’re not too keen on the consistency of soft onions in soup, you can simply use a hand blender to puree the soup smooth.

    Nutrition

    Calories: 117kcalCarbohydrates: 27gProtein: 3gFat: 1gSaturated Fat: 1gCholesterol: 1mgSodium: 1018mgPotassium: 375mgFiber: 4gSugar: 13gVitamin A: 533IUVitamin C: 19mgCalcium: 66mgIron: 1mg
    Keyword crockpot, egg free, gluten free, nut free, onion soup, slow cooker, soy free
    Tried this recipe?Mention @hintofhealthyfood or tag #hintofhealthy!

    More Healthy slow cooker soup recipes

    • Slow Cooker Ham and Potato Soup
    • Crockpot Cabbage Roll Soup
    • Slow Cooker Pumpkin Soup
    • Slow Cooker Leek and Potato Soup

    Latest Recipes

    Sauteed sweet potatoes on a plate.

    Sauteed Sweet Potatoes

    Orzo Pesto Salad in a bowl.

    Orzo Pesto Salad

    Brussels sprouts in slow cooker.

    Slow Cooker Brussels Sprouts

    Christmas morning punch with cranberries.

    Christmas Morning Punch

    Reader Interactions

    Leave a comment Cancel reply

    Your email address will not be published.

    Recipe Rating




    Primary Sidebar

    Hi, I'm Tonje! I make easy and healthy everyday recipes that your family will love. Browse my recipe collection to discover new favorites, and make sure to let me know what you think!

    More about me →

    Popular Recipes

    • Air Fryer Eggplant
    • Mediterranean Roast Vegetables
    • Crepes with Almond Milk
    • Air Fryer Pork Roast
    • Slow Cooker Beef Stew
    • Air Fryer Tilapia

    As Seen In

    Hint of healthy as seen in

    Footer


    2022 © Hint of Healthy Privacy Policy Disclaimer Contact About