This post may contain affiliate links. Please read my disclosure policy.
My Easy Crock Pot French Onion Soup is truly so easy with only seven ingredients AND it’s budget friendly too! Perfect for a weeknight meal or company-worthy, caramelized onions and melted swiss and gruyere cheese on crusty bread make this soup extra special!
Why We Love This Soup
I have always loved a good French onion soup. I will often order it when it’s the soup of the day at any restaurant. So, several years ago when I brought home several pounds of sliced onions from an event I helped with at my kids’ school, I went on the hunt to find a good recipe that I could make at home.
That’s where this Easy Crock Pot French Onion Soup comes in! I wanted something that was simple and since I love my slow cooker, developing a recipe that would work that way was also part of my criteria.
I love slow cooker soups because the make my life so easy. A couple of other favorites include Crock Pot Lasagna Soup and Ground Turkey, Vegetable and Barley Soup.
With only seven ingredients, my version of French Onion Soup is not only SO EASY but also nice enough to serve for company. It is also budget friendly because it uses easy to find and economical ingredients.
The original recipe I used called for white wine and that makes it traditional but at the time, I only had red wine on hand to I figured with the beef broth, it would make for a great flavor combination!
I have made this soup with both white and red wine and they are both delicious. We found using the red wine gave the soup a richer taste but the white wine was also yummy. Just use what you have on hand!
How Did This Soup Get It’s Name?
You may have guessed it but French Onion Soup gets it’s name because it originated in France. While some versions of this soup have been made for centuries, French onion soup as we know it today came about in the 18th century.
There are a few different variations as to how the French claimed this soup as their own, both with ties to King Louis XV. At some point, the French decided to caramelize the onions first to bring out their sweet flavor.
Nowadays we know this soup as a beef stock based soup served with croutons or crusty bread and cheese. It gained popularity in the United States in the 1960s due to an increased interest in French cuisine.
Ingredient Tips For This Recipe
As mentioned, the ingredients for this simple soup are easily found at the grocery store but I do have a few tips for you!
I have used both fresh or frozen sliced onions. Sometimes when there is a great sale on onions, I will slice up a bunch and freeze them to use in recipes like this one or Slow Cooker Beef and Chicken Fajitas. Since they are being cooked, the texture works just fine in most recipes!
We like to buy the skinny baguette bread from our local grocery store’s bakery department. You can use day old bread too! The skinny loaves of bread are perfectly sized for a bowl of soup but you can use any sort of crusty French style bread if you like.
The shredded Swiss cheese can often be a little trickier to find. But most grocery stores have it in the shredded cheese section. You could also buy a block of Swiss cheese and shred it yourself.
But my favorite place to find shredded Swiss cheese is at ALDI! They have a Swiss and Gruyere cheese blend that is perfect for this soup and at a great price. If you have an Aldi store near you, be sure to check for it there!
Simple Steps To Make This Soup
One thing I want to mention about making this French onion soup is that while it is super simple, the prep takes a little bit of time because you are caramelizing the onions first. The good news is that cooking the onions is mostly hands-off cooking. So you can be prepping the other ingredients or even cleaning up the kitchen while it is cooking.
Start by melting the butter in a large skillet (affiliate link) and add the sliced onions (1).
Cook the onions until they are soft and golden (2). I like to use a spatula or even non-stick tongs (affiliate link) to make sure the onions are getting stirred well enough that all sides can caramelize.
Next, add the onions and remaining ingredients to a large slow cooker (3). I use a 6-quart slow cooker (affiliate link) for this recipe.
Before I put on the lid, be sure to stir everything well in the slow cooker (4), set it for the desired cooking time (based on whether you’re cooking it on HIGH or LOW) and that’s it!
Make Ahead Tips
There are a couple of simple make ahead tips for this French onion soup.
You can sliced the onions ahead of time using a large chef’s knife or slicer on a food processor (affiliate link). Store the sliced onions in the refrigerator for up to a week or in the freezer for up to three months. Be sure to date and label (affiliate link) the container if you are freezing.
Another simple thing to do is to slice and freeze the French baguette. This is especially helpful if you are not serving too many people and the bread is more than your family can use at one time (they are long loaves of bread!). The bread can be frozen for up to three months if in a freezer safe bag or container. Be sure to squeeze out as much air from the bag or container to avoid freezer burn.
Is this Soup Freezer Friendly?
I’ve never frozen this soup so I’m not sure how it would do but I imagine since the onions are cooked and tender from the prep, it should be just fine. I love using Souper Cubes (affiliate link) to freeze and store soup easily in my freezer. Don’t forge to date and label (affiliate link) you soup container!
More Simple Soup Recipe Ideas
Have I said I love soup?!? It’s true. Here are a few more favorite soup recipes of ours:
Easy Crock Pot French Onion Soup
- 4 tablespoons butter divided
- 8 cups yellow onions sliced (about 3 pounds)
- 1 tablespoon granulated sugar
- ¼ cup dark red wine such as Merlot
- 8 cups beef broth
- 16 slices French bread
- ½ cup shredded Swiss cheese or substitute Gruyere
- In a large skillet, melt butter over medium to low heat.
- Add onions and cook just until onions are limp and transparent but not brown, about 10 minutes, stirring frequently.
- Sprinkle sugar over onions and cook, stirring until onions are brown and caramelized, about 8-10 minutes.
- Transfer onions and any brown bits into 6 quart slow cooker.
- If desired, add wine to skillet and return to the heat. Bring wine to a boil, scraping any brown bits with a non-stick spoon or spatula. Transfer wine to slowcooker with onions and add beef broth.
- Cover and cook on HIGH 4 hours or LOW for 8 hours.
- When ready to serve, preheat oven broiler.
- Place individual oven-safe bowls on a large baking sheet and ladle the soup.
- Top with a slice of bread and cover with cheese, about 1-2 tablespoons.
- Place tray with bowls under the broiler until cheese is golden brown, melted and bubbly—about 3 minutes
- Alternatively, you can place sliced bread pieces on a baking sheet and top with shredded cheese. Then broil until cheese is golden brown. Once done, transfer to bowls of soup and serve.
Originally published in September 2015 and updated in November 2020 with new photos, video and content.
Be sure to check out my Amazon Shop to discover the many items I use in my own kitchen. Meal Planning Magic is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. Ordering products mentioned here are at no extra cost to you. Thank you for your support.
When is beef broth added? It’s not stated in recipe.
Meal Plan Mom (Brenda)
Hi Maria! I updated the recipe to add that–thanks for the catch! You add the beef broth to the slowcooker just before you set it to cook for the 8 hours. Hope you enjoy the soup.
when I make french onion soup I usually use brandy, cognac or sherry will have to try wine next
Meal Plan Mom (Brenda)
That sounds good too! I will have to give one of those a try.