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Slowly caramelized onions are the secret to delicious Soupe à L’oignon Gratinée (better known on this side of the pond as French Onion Soup).
Cold winter months call for warm, steamy soups and a crock of French Onion Soup topped with toasted croutons and Gruyere will certainly warm the soul on a chilly day.
This classic soup originated in Paris in the 18th century, but became popular in the U.S. in the 1960s thanks to the endearing TV chef, Julia Child.
Slowly cook thin sliced onions in butter until they are soft-tender and reach a beautiful golden (caramel) color. This usually takes about 30 minutes—don’t try to rush the process!
Once you master caramelized onions, you’ll want to try them on burgers, grilled sandwiches, or even as a salad topping—so flavorful and so delicious!
Once the soup is prepared, ladle it into piping hot in oven-safe soup bowls or soup crocks which are placed on a baking sheet. Next, top them off with toasted croutons or a slice of thick, crusty bread.
Personally, I like to top the soup with a handful of one-inch croutons that I cut from a baguette. This seems a bit easier to eat than the slice of bread, but either is fine.
Sprinkle the top with Gruyere and pop under the broiler to until the cheese melts and is bubbly—be generous with the cheese!
With each bite, the cheesy bread “sops” up the flavorful broth and onions. It’s almost like au jus, only much, much better and much quicker to prepare!
The stock for the soup is a combination of beef and chicken broths (packaged broth is perfectly fine in this recipe) and a cup of dry red wine.
This, along with the slow-cooked onions, simmers into a splendid blend of flavors that pairs perfectly with the Gruyere cheese. Bon Appétit!
French Onion Soup
- 1/2 cup unsalted butter
- 4 large onions sliced
- 2 garlic cloves chopped
- 2 bay leaves
- 2 fresh thyme sprigs
- Kosher salt and freshly ground black pepper
- 1 cup red wine
- 3 tablespoons all-purpose flour heaping
- 1 qt. beef broth
- 1 qt. chicken broth
- 1 baguette sliced
- 5 ounces grated Gruyere
- Melt butter in a large pot over medium heat, then add sliced onions, garlic, bay leaves, thyme, and salt and and pepper. Cook for 25 minutes or until the onions are golden, soft, and caramelized.
- Add the red wine and bring to a boil. Reduce heat and simmer for 5 more minutes, until the wine has evaporated and the onions are mostly dry.
- Discard the bay leaves and thyme. Sprinkle flour over the onions and stir. Reduce heat down to medium low and cook for 10 minutes. Add the beef and chicken broths and bring to a simmer, Cook for 10 minutes then season with salt and pepper, to taste.
- Cut the baguette into slices or large croutons. Place on a baking sheet and lightly toast.
- To serve, ladle soup into oven-safe bowls and top with the toasted bread. Sprinkle generously with the Gruyere and broil until bubbly and golden brown, 3 to 5 minutes.