Bistro-style French Onion Soup made easy in the slow cooker! You'll love how simple it is to make while you spoon up bites of sweet and savory onion, rich beef broth, hearty bread and gooey melted cheese.
Course Soup
Cuisine French
Keyword crock pot french onion soup, french onion soup, slow cooker french onion soup
Prep Time 10 minutesminutes
Cook Time 18 hourshours
Total Time 18 hourshours10 minutesminutes
Servings 8servings
Calories 426kcal
Author Lauren
Ingredients
3poundssweet onionssliced in half-moons
2tablespoonsunsalted buttermelted
2tablespoonsolive oil
½teaspoonsalt
¼cupbrandy
8cupsbeef broth
4sprigs of thyme
2bay leaves
½teaspoonchopped garlic
salt and pepperto taste
1loaf sourdough breador another hearty bread like baguette or ciabatta
½poundGruyere or Swiss cheesefresh grated
Instructions
Caramelize the onions. Slice the onions into thin half-moon slices. In the slow cooker, combine the onions, butter, olive oil, and salt. Cook on low for 10 to 12 hours.
Make the soup. Once the onions have cooked down, add the brandy, beef broth fresh thyme, bay leaves, and garlic.
Cook the soup. Cook on low for 8 hours or high for 4 hours. Season with salt and black pepper to taste.
Toast and broil. Just before the soup is done cooking, slice the bread into 2 to 4 inch wide slices, and grate the cheese. Toast the bread until golden brown. Ladle the soup into oven-safe bowls, top with toast and grated cheese. Set all the bowls on a sheet tray and broil on high for 3 to 5 minutes until the cheese is melted and starting to brown. Serve immediately.
Notes
Onions can be caramelized in advance and then used to make the soup when you're ready.
There two options for timing to cook the soup. Option 1: Cook the onions overnight for 10 to 12 hours. In the morning, add the soup ingredients and cook on low for 8 hours or high for 4 hours. Option 2: Set the onions to cook in the morning all day, then make the soup and high cook for 4 hours for dinner.