French Onion Soup

A dish dating back to the 18th century and made from beef broth, and caramelized onions this soup saw a resurgence in America in the 1960s because of a culinary curiosity with French food. This version uses mozzarella cheese rather than the traditional gruyère melted on top and is cooked in a slow cooker. So you can pretty much turn it on in the morning and enjoy it in the evening. Adapted from "Crockpot French Onion Soup" found on How Sweet it Is Blog which was adapted it from Tyler Florence's recipe.

Prep Time: 30 minutes
Cook Time: 8 hours
Yield: One giant pot
Serving Size: 8-10


  • 4 medium, or 3 large onions, thinly sliced
  • 3 garlic cloves, minced
  • 4 tbsp of butter
  • 2 tbsp balsamic vinegar
  • 2 tbsp brown sugar
  • 3 tbsp flour
  • 12 ounces of beer
  • 64 ounces of low-sodium beef stock (I used Bovril beef base: I added 4 tbsp to the boiling water.
  • 2 tbsp fresh thyme
  • ½ tsp black pepper
  • ½ tsp salt
  • French bread
  • Mozzarella cheese sliced


  1. Set your slow cooker on high, then add onions, garlic, brown sugar, butter, salt and balsamic and mix until combined. Cover and let cook for 60 minutes, stirring occasionally, until onions are a bit caramely and brown on the edges. Add in flour, then stir thoroughly and let sit for 5 minutes. Add in beer, beef stock, thyme, and pepper, then turn heat down to low, cover and cook for 6-8 hours.
  2. Before serving, cut french bread or baguette into slices. Fill soup bowls to the top, then cover with slice of bread and a slice of cheese. Set under the broiler for 2-3 minutes, or until cheese is bubbly and golden brown. Be careful when serving as bowls will be hot! Bon appetite!

Used in This Dish