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–+ servings
French Onion Tomato Soup
French Onion Tomato Soup is a cozy fusion of two beloved comfort foods: the savory depth of French onion soup and the bright acidity of tomato soup. The caramelized onions provide rich, umami notes while the tomato base adds brightness. Topped with toasted French bread and melted Swiss cheese, this hearty bowl makes a warming meal perfect for cold evenings or casual dinner gatherings.
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Prep Time 15 minutes
Cook Time 40 minutes
Total Time 55 minutes
Course Soup
Cuisine Fusion
Servings 6
Calories 295 kcal

Ingredients
  

  • ⅓ cup butter (or 1/4 cup)
  • 4 yellow onions (large, sliced (or 3 large onions))
  • 1 tbsp flour (scant)
  • 1 ½ tsp salt (or 1 ¼ tsp)
  • 12 oz tomatoes (1 can)
  • 6 slices French bread (toasted )
  • 2 cups Swiss cheese (grated )

Instructions
 

Step 1: Sauté Onions

  • Melt butter in a large pot.
  • Add sliced onions and sauté until golden, about 15 minutes.

Step 2: Make the Base

  • Sprinkle flour over onions and cook briefly.
  • Add salt and tomatoes (including liquid).
  • Simmer covered for 10 minutes.

Step 3: Blend and Heat

  • Blend the mixture until smooth using a blender or food processor.
  • Return to the pot and heat for 15 more minutes on low.

Step 4: Prepare to Serve

  • Preheat broiler.
  • Pour hot soup into 6 heatproof bowls or a large shallow casserole.
  • Place a slice of toasted French bread on top of each.

Step 5: Add Cheese and Broil

  • Sprinkle grated Swiss cheese evenly over the bread.
  • Place under the broiler for 3–5 minutes, or until the cheese melts and begins to brown.

Tips

  • Use sweet onions for a milder, more caramelized flavor.
  • Replace Swiss cheese with Gruyère for a more traditional French onion style.
  • Add a splash of white wine while cooking the onions for extra depth.
  • Use homemade beef or vegetable broth for richer flavor.
  • Toast the bread under the broiler for extra crunch.
  • Add fresh herbs such as thyme or parsley for aroma.
  • Substitute canned tomatoes with fresh peeled tomatoes for a brighter taste.
  • For a heartier version, add cooked rice or small pasta.
  • Make it vegetarian by using vegetable broth and vegetarian cheese.
  • Add a pinch of smoked paprika for warmth.

Nutrition

Calories: 295kcalCarbohydrates: 22gProtein: 11gFat: 19gSaturated Fat: 12gPolyunsaturated Fat: 1gMonounsaturated Fat: 5gTrans Fat: 0.3gCholesterol: 55mgSodium: 720mgPotassium: 360mgFiber: 3gSugar: 9gVitamin A: 750IUVitamin C: 14mgCalcium: 260mgIron: 1.7mg
Keyword comfort food, French soup, heirloom recipe, homemade soup, nostalgic food, onion soup, rustic recipes, tomato soup, vintage recipe
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