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french onion soup
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French Onion Soup Recipe

french onion soup with pancetta
Prep Time5 minutes
Cook Time3 hours
Total Time3 hours 5 minutes
Course: Soup
Cuisine: French
Servings: 6 people
Calories: 609kcal
Author: Cari


  • 3 oz of minced Pancetta
  • 1 tablespoon unsalted butter
  • 5 Large yellow Sunion Onions about 3 pounds, peeled and sliced thin*
  • ½ Teaspoon coarse salt
  • 2 Cups low-sodium chicken broth
  • 4 Cups low-sodium beef broth
  • ½ Cup of white wine I used Pinot Grigio
  • 2 Sprigs fresh parsley
  • 2 Sprig fresh thyme
  • 2 Bay leave
  • 1 tablespoon good-quality balsamic vinegar
  • ½ teaspoon of garlic powder
  • Salt and black pepper
  • 1 French baguette loaf cut on the bias into ¾-inch slices
  • 1 Lb. of sliced mozzarella cheese
  • 3 Oz. Asiago cheese grated
  • 3 Oz. of Gruyere cheese grated


  • Cut off the stem and root ends of the onions, then halve then lengthwise, and peel away the dried skin.  Cut the onions into thin slices. It’s important to have all the onion slices roughly the same size so they cook evenly.
  • Cook the pancetta fully in a dutch oven. Once cooked, remove the pancetta using a slotted spoon from the dutch oven and reserve for later. You’ll have some delicious pancetta oil at the bottom of the pot and add to that your unsalted butter. Add sliced onions, salt, stirring to coat onions thoroughly with the butter/oil. Cook, stirring frequently, until onions are reduced and syrupy and inside of pot is coated with very deep brown crust, approximately 2 hours.
  • Stir in chicken and beef broths, wine, and be sure to scrape the bottom of the pot with a wooden spoon to scrape off all those delicious brown bits. Add parsley, thyme, and bay leaf and cooked pancetta then bring to a simmer.  Simmer to blend flavors, approximately 30 minutes. Remove herbs and discard. Stir in balsamic vinegar and adjust seasonings with garlic, salt and pepper to taste. At this point, the soup can be cooled to room temperature and refrigerated in an airtight container up to 2 days.  To use, return to simmer before finishing soup with croutons and cheese.
  • Preheat oven to 400 degrees F.  While the soup simmers, toast your baguette. Lightly brush the baguette pieces with olive oil and arrange the baguette slices in single layer on baking sheet and bake until the bread is dry, crisp, and golden at edges, about 10 minutes. Set aside until ready to use.
  • When ready to serve the onion soup, adjust oven rack to upper middle position; heat the broiler. Set onion soup bowls on baking sheet and fill each with about 1 ½ cups soup.  Top each bowl with toasted baguette slices that cover the top of the bowl without overlapping the bread. Over the bread lay the mozzarella in a single layer. Besure to slightly overlap the cheese over the edge of the bowl. This acts as a delicious little safety net that keeps the grated cheese from falling into the soup abyss
  • Sprinkle the top of each with about 2 tablespoons grated Asiago cheese and 2 tablespoons Gruyere cheese.  Place the bowls into the oven, about 5 to 6 inches from the broiler and let broil until cheese is brown and bubbly, about 10 minutes. Remove from oven and serve immediately.


The cheese layer should cover the whole surface, so it will stick to the sides and form a crust that holds its shape and does not sink.

Substitutions and Variations

Want a vegetarian french onion soup? Instead of pancetta oil drippings, cook the onions in vegetable oil. Omit the pancetta Swap your broth for vegetable stock and adjust salt to your preference
Want a keto/low carb french onion soup? Simply omit the baguette in the soup.


Place the french onion soup in an airtight container and place in the refrigerator. It will keep in the fridge for upto 4 days. When ready to consume, place the soup in oven safe bowls and top with toasted baguette and cheese.
If you wish, you can freeze this soup. Portion the soup into individual portions and place them in an airtight container; place in the freezer for upto 1 month.


Serving: 1cup | Calories: 609kcal | Carbohydrates: 34g | Protein: 37g | Fat: 35g | Saturated Fat: 19g | Polyunsaturated Fat: 3g | Monounsaturated Fat: 11g | Trans Fat: 1g | Cholesterol: 99mg | Sodium: 1615mg | Potassium: 702mg | Fiber: 3g | Sugar: 6g | Vitamin A: 867IU | Vitamin C: 8mg | Calcium: 756mg | Iron: 2mg