Crockpot French Onion Soup is perfect for chilly nights or when you want to enjoy a delicious, hearty meal. It's made with simple ingredients and almost no prep time!
Spray the inside of the slow cooker with no-stick cooking spray.
Peel and quarter onions. Mince garlic.
Add the onions, garlic, butter, salt, and pepper.
Cover and cook on high for 1 hour, until the onions have started to soften.
Add the beef broth, set the crockpot to low, cover and cook for 6-7 hours.
During the last 20-30 minutes, preheat the oven to 350* Fahrenheit.
Portion the soup into oven safe bowls, placed on a rimmed baking sheet.
Top each bowl with slices of toasted baguette and provolone cheese.
Bake for about 10 minutes, or until the cheese is completely melted.
Switch the oven to broil and broil until the cheese is bubbly and browned, about a minute or two (watch closely so you don’t burn the cheese).
Serve immediately and enjoy!
Notes
Storage:Store the cooled soup in an airtight container—be sure to leave the bread slices and cheese off. Refrigerated, the leftovers will keep for about three days.Three days not long enough? Good news! This homemade French onion soup recipe freezes great! Portion it into freezer-safe containers and store for up to three months.Let the soup thaw in the refrigerator, or speed up the process using the microwave. Then, reheat it to simmering perfection either on the stovetop or again in the microwave.Tips
If you don't have oven-safe bowls, place the bread slices on a cookie sheet. Top them with the cheese and bake. Then, carefully use a spatula to place each piece of cheesy bread on top of the soup.
Don't skip steps. Cooking the onions with butter (without broth) allows them to caramelize. This gives your French onion soup its flavor!
Adding a pinch of brown sugar helps the onions caramelize a bit more. However, this does sweeten the soup so proceed cautiously!
If you want, you can caramelize your onions in a large skillet over low heat on the stovetop. This process can take around 45 minutes, though, so that's why I prefer to let the crockpot do the work!
Cheese goes from golden brown to burnt within seconds, so watch it carefully under the broiler.
The 6-8 hour setting on low helps all the flavors develop perfectly. If you really need to, though, you can get away with cooking it for 3-4 hours on high.