Ingredients:

  • 5 lbs yellow onions, thinly sliced
  • 2 tbsp extra virgin olive oil
  • ½ tsp baking soda
  • 1 tsp salt
  • 6 cups low-sodium beef stock
  • ½ cup dry white wine
  • 3 cloves garlic, minced
  • 1 tbsp fresh thyme leaves
  • 2 bay leaves
  • ½ tsp black pepper
  • 1 French baguette, sliced into 1-inch rounds
  • 1 ½ cups shredded Gruyère cheese
  • ¼ cup grated Parmesan cheese

Instructions:

  1. Heat olive oil in a Dutch oven over medium heat. Add the sliced onions and salt. Stir in the baking soda and cook, stirring occasionally, for 30–40 minutes until the onions are a deep, mahogany-colored jam.
  2. Stir in the minced garlic and thyme, cooking for 60 seconds until aromatic.
  3. Pour in the white wine to deglaze the pan, scraping all the browned bits from the bottom.
  4. Pour in the beef stock and add the bay leaves. Simmer on low for 20 minutes.
  5. Preheat the broiler. Toast the baguette slices in the oven for 3 minutes per side until crisp.
  6. Ladle the soup into oven-safe crocks, place a toasted bread slice on top, and top with Gruyère and Parmesan cheese.
  7. Broil for 2–4 minutes until the cheese is bubbling and golden-brown.