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This delicious soup can be made in a slow cooker and is packed with flavor!

Slow Cooker French Onion Soup Recipe
Love that this soup cooks all day in a slow cooker! It does take some prep work, but the taste is well worth it!
Serving people
Ingredients
- ¾ cup butter
- 4 yellow onions, sliced thinly into rings
- 1 Tablespoon white sugar
- 2 cloves garlic, minced
- ½ cup apple cider
- 7 cups beef broth
- ¼ teaspoon thyme
- 1 loaf french bread, sliced into 1" slices
- ½ cup Provolone cheese
- ½ cup swiss cheese
- ½ cup Mozzarella cheese
Equipment
Instructions
- In a large skillet on medium-high heat, melt butter. Add in onions and cook until see-through, stirring frequently (It takes about 10 minutes).
- Add in sugar, and reduce heat to medium. Stir the onions constantly, caramelizing them. It will take about 20-30 minutes.
- Add in the minced garlic and apple cider, and stir until warmed through.
- Transfer the onions to the slow cooker and add in beef broth and thyme. Cook on low for 6-8 hours.
- Before serving, place the french bread slices on a baking sheet and broil in the oven for 1-2 minutes (just until browned).
- In a small bowl, mix together the three cheeses.
- Pour soup in oven-safe bowls (the soup will serve 6-8), place a piece of french bread in each bowl, and then top each with a portion of cheese. Place each bowl on the cookie sheet, and broil for 2 more minutes, until the cheese starts to melt and brown.
- Serve hot.
Nutrition
Calories: 564 kcal · Carbohydrates: 50 g · Protein: 19 g · Fat: 32 g · Saturated Fat: 20 g · Trans Fat: 1 g · Cholesterol: 84 mg · Sodium: 1762 mg · Potassium: 404 mg · Fiber: 3 g · Sugar: 9 g · Vitamin A: 949 IU · Vitamin C: 6 mg · Calcium: 275 mg · Iron: 3 mg
Did You Make This Recipe?We’d love to hear your thoughts! Leave a review or a question in the comment section below the post.




















After their time in the skillet, when you transfer the onions to the slow cooker, do you leave behind the garlic and apple cider vinegar or do you dump the whole skillet into the slow cooker? This looks delicious!!
Dump everything from the skillet into the slow cooker!
This looks great! Your recipe calls for apple cider, is that the drink or is it apple cider vinegar?
It’s apple cider that is found on the juice aisle.
Do you ever list the nutrition information on your recipes? They always sound so good but I am cooking for a child with diabetes and don’t know what the carbs count. Does the bundle of e books that you are selling now have the carbs listed? Would love to get them
I’m excited to try this recipe. You say 4 slices yellow onions, but can you put that into cups? Like how many cups of sliced onions. Asking since sometimes they are small and sometimes they’re gigantic.
Maybe a 3-4 inch onion in diameter. You can really add as much as you like. Use 4 slices from the center of the onion where it is the biggest and break up the slices. But if you love onion, add a little more.
Can this recipe be made in an instant pot?
You can easily adapt slow cooker recipes to the Instant Pot. Here is a youtube link to watch. It’s a video we made. https://youtu.be/8DKWGgsKY9s