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French Onion Casserole

A delightful dish featuring layers of caramelized sweet onions and savory broth, topped with toasted baguette slices and bubbling cheese.
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Prep Time 30 minutes
Cook Time 1 hour
Total Time 1 hour 30 minutes
Servings: 6 servings
Course: Dinner, Main Course
Cuisine: French
Calories: 375
Ingredients Method Notes

Ingredients
  

Main Ingredients
  • 3 medium sweet onions, sliced These onions become tender and caramelized, releasing their natural sweetness.
  • 3 tablespoons salted butter Provides a rich, creamy base for sautéing the onions.
  • 4 cups beef broth Use high-quality broth for a deep flavor. Substitute with vegetable broth for a vegetarian version.
  • 1 teaspoon Worcestershire sauce Adds an umami depth to the dish.
  • 4 ounces French baguette bread, sliced about ½-inch Provides a satisfying crunch on top of the casserole.
  • 1 cup shredded mozzarella cheese Melts beautifully and adds creamy goodness.
  • ¼ cup grated Parmesan cheese Adds a sharp, nutty flavor that complements the mozzarella.
  • Optional garnish: chopped fresh thyme or parsley Provides a fresh herbal touch.

Method
 

Preparation
  1. Preheat the oven to 350°F (175°C). Grease a medium casserole dish and set it aside.
  2. In a large saucepan, melt the butter over low heat.
  3. Add the sliced onions to the melted butter and cover the pot. Cook gently for about 30 minutes, stirring occasionally, until soft and caramelized.
Cooking
  1. Once the onions are golden, add the beef broth and Worcestershire sauce; bring to a boil.
  2. Reduce heat to low and simmer, uncovered, for another 30 minutes.
  3. Pour the onion and broth mixture into the prepared baking dish.
  4. Lightly toast the baguette slices until crisp but not burned.
  5. Arrange the toasted bread slices on top of the onion mixture.
  6. Cover the bread with mozzarella and sprinkle Parmesan over the top.
  7. Bake uncovered for 20-30 minutes, or until the cheese is melted and lightly browned.
  8. Garnish with fresh herbs if desired and serve hot.

Notes

For more flavor, add a splash of sherry vinegar or balsamic vinegar to the onion mixture. Use pre-sliced onions or onion powder for convenience. Experiment with different cheeses like Gouda or cheddar.