Ingredients:

  • 2 ½ lbs Yellow or Spanish Onions, thinly sliced
  • 1 Tbsp Olive Oil
  • 1 Tbsp Unsalted Butter
  • 1 tsp Fine Sea Salt
  • ½ tsp Freshly Cracked Black Pepper
  • 1 Tbsp All-Purpose Flour (or cornstarch for gluten-free)
  • ½ cup Dry White Wine (e.g., Sauvignon Blanc)
  • 6 cups Low-Sodium Beef Stock
  • 1 Bay Leaf (dried)
  • ½ tsp Dried Thyme
  • 1 tsp Worcestershire Sauce (optional)
  • 4 slices Baguette, cut ¾ inch thick
  • 4 oz Gruyère Cheese, freshly grated
  • Pinch of Paprika or Cayenne Pepper (optional)

Instructions:

  1. Slice the onions thinly and uniformly. Uniformity is key for even cooking.
  2. In a large Dutch oven, combine the olive oil and butter over medium-low heat.
  3. Add all the sliced onions, salt, and pepper. Stir well to coat.
  4. Sweat and Soften (15 minutes): Cook uncovered, stirring occasionally, until the onions have released their liquid, softened, and are translucent. Keep the heat low.
  5. Caramelise (45–60 minutes): Reduce the heat to low. Stir frequently (every 5-10 minutes initially, then every 2-3 minutes as they deepen in colour). Cook until the onions reach a deep, rich, mahogany brown colour. If the pan develops a sticky brown layer (fond), deglaze lightly with 1-2 tablespoons of water, scrape up the fond, and continue cooking.
  6. Dust with Flour: Once the onions are perfectly caramelised, sprinkle the flour evenly over them. Stir constantly for 1 minute to cook out the raw flour taste.
  7. Deglaze with Wine: Pour in the dry white wine. Increase the heat slightly and scrape the bottom of the pan thoroughly to lift any remaining fond. Let the wine simmer and reduce by half (about 2 minutes).
  8. Add Stock and Simmer: Pour in the low-sodium beef stock, add the bay leaf, thyme, and Worcestershire sauce (if using). Bring the soup to a gentle simmer.
  9. Rest and Taste: Reduce heat to low, cover partially, and let simmer for 20-30 minutes to allow the flavours to marry. Remove the bay leaf and thyme sprig before serving. Adjust salt and pepper as needed.
  10. Prepare Croutons: While the soup simmers, lightly toast the baguette slices until crisp, either in a toaster or under the broiler for 1-2 minutes.
  11. Assemble Bowls: Preheat the broiler (grill) to medium-high. Ladle the hot soup into the oven-safe crocks.
  12. Top and Broil: Place one toasted baguette slice on top of the soup in each bowl. Pile the grated Gruyère evenly onto the bread and sprinkle lightly with paprika (if using).
  13. Melt and Brown: Place the crocks onto a baking sheet. Broil for 2-4 minutes, watching constantly, until the cheese is bubbling, melted, and golden brown with blistered edges.
  14. Serve Immediately: Carefully transfer the bowls to serving plates.