Slow Cooker Beefy French Onion Soup is the most amazing onion soup recipe! Shredded beef and cheese in a homemade beef stock, this is total comfort food.
The Best French Onion Soup Recipe
If that weren’t enough to get you to make this Slow Cooker Beefy French Onion Soup, I’ll give you the story behind it too.
We were just on a family vacation in St. John. Just in November but it already seems so long ago…the fact that we woke up to 6 degrees here in Jersey today isn’t helping at all.
One night though we made our way through town and ate dinner at a restaurant called Extra Virgin Bistro. It was a really nice, open air restaurant that served upscale Italian food.
First glance at the menu I knew we were in the right place, but the one thing I knew I had to order was the French Onion Soup.
Because it had shredded short ribs in it (why? because they must follow the way I think in that everything is better with meat) and it was ridiculously good.
So, you know we had to come home and try our best to make it again – and we totally nailed it.
How Do You Make Slow Cooker Onion Soup?
I’m going to tell you right off the bat, this is a two day recipe. It’s not a quick one but it is still an easy one. Also I can promise you that it’s SO worth every minute that it takes to make.
We use our slow cooker for lots of soup recipes like this Turkey Leg Split Pea Soup. That one doesn’t take two days so check it out if you’re shorter on time…
Making the stock in the slow cooker is the first step of the process. Everything goes in the pot and it cooks for 8 hours on low.
We had a large prime rib for one of our holiday dinners so we actually used the ribs cut off from that to make this soup, but seeing as you probably won’t have those laying around – short ribs are the way to go.
As you can see we like our soup beefy, just like our popular Beefy Tomato Soup recipe…lots of beef.
You can remove the ribs at this point, strain the broth into a stock pot and shred the beef from the bones into a bowl.
Put the stock pot in the fridge to chill overnight and separate the fat from the broth. This step is really important, short ribs are fatty so if you don’t do this part you’ll end up with really greasy soup.
When you’re ready to make the rest of the soup, carefully peel the layer of fat off the top of the stock and set the pot over medium heat to simmer.
While that’s simmering away, you can make the caramelized onions. So were you wondering when the onions were going to come into this onion soup recipe???
Here they come! So it will take you about 20-30 minutes to get the onions soft and caramelized, but it’s another step you don’t want to skip.
When the onions are done you can add them to the stock that’s been simmering, along with the shredded beef.
Grab a few oven safe bowls and put them on a sheet pan. Fill the bowls with the soup and top with a piece of toasted baguette and all the cheese you want.
Under the broiler it goes for a few minutes until the cheese melts and starts to brown…then this onion soup is ready.
This Slow Cooker Beefy French Onion Soup recipe is worth the wait. Hopefully you have enough for the next day, too because the leftovers are even better.
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This slow cooker french onion soup is so rich and hearty, the homemade beef stock is so worth making!
For the Stock
- 3 lbs. short ribs, seasoned with salt and pepper
- 1 tablespoon kosher salt
- 2 sprigs fresh tarragon
- 1 teaspoon peppercorns
- 1 teaspoon dried parsley
- 1 teaspoon dried thyme
- 5 carrots, peeled and cut into large pieces
- 2 medium onions, peeled and quartered
- 5 celery stalks, cut into large pieces
- 10 cups water
For the Caramelized Onions
- 6 medium to large onions, peeled, cut in half and sliced
- 2 tablespoon butter plus 1 tablespoon olive oil
- 1 teaspoon salt
- 1/2 teaspoon dried thyme
- 1/4 cup marsala wine
- 4 cups gruyere cheese, shredded
- 1 french baguette, sliced and lightly toasted (you’ll need 2 pieces for each bowl of soup)
- Preheat the oven to 425 degrees. Place the seasoned ribs on a sheet pan, drizzle with olive oil and roast for 45 minutes, turning once half way through cooking.
- Once the ribs are roasted, place them into a slow cooker along with the rest of the ingredients for the stock and set on low heat for 8 hours.
- Remove the bones from the stock and place into a bowl to cool.
- Shred the meat from the bones, discarding any fat and set aside.
- Carefully pour the stock through a strainer into a large pot. You can throw the out the vegetables used in the stock.
- Once the stock has cooled, cover and place in the refrigerator overnight.
- When you’re ready to make the soup, remove the layer of fat from the stock and discard.
- Place the pot over medium heat (uncovered so the stock reduces) and bring to a boil. Turn down and let simmer while you make the onions (about 30 minutes).
- Add the butter and olive oil to a large skillet along with the sliced onions over medium-low heat.
- Add the salt and thyme and stir to combine.
- Let the onions cook, stirring often, for at least 30 minutes until the onions are brown and caramelized. The time it takes to caramelize will depend on the size of the skillet you are using, but they should be completely soft and brown in color when they are done. After the 30 minutes are up and the onions are caramelized, add the marsala wine and cook another 5 minutes.
- Now add the onions to the simmering stock along with the beef you removed from the bones.
- Stir and let simmer for another 15 minutes, then test for seasonings.
- Preheat the broiler.
- Fill each oven proof bowl with onion soup, then top with one or two pieces of toasted bread.
- Cover the bowl with cheese then repeat with the remaining soup bowls.
- Place the bowls on a sheet pan under the broiler for 3-4 minutes until the cheese melts and starts to get toasty on top.
- Remove from the oven and serve piping hot!
You’ll need oven safe bowls or soup crocks for this recipe!
- Category: soup
- Method: slow cooker/stove top
- Cuisine: American
Keywords: french onion soup, onion soup, soup recipe, slow cooker soup, slow cooker onion soup, beef recipes, short ribs, gruyere cheese