- 2 tablespoons olive oil
- 8 onions, thinly sliced (preferably 3 yellow onions, 3 white onions and 2 red onions)
- 6 cloves garlic, chopped finely
- 1 stick butter
- 1/2 cup whiskey, plus more
- 1 bay leaf
- 5 sprigs thyme, leaves only, or 2 teaspoons dried thyme
- 8 cups chicken stock
- 16 (1/4-inch-thick) slices day-old French baguette
- 15 ounces Gruyère cheese, cut into 1/8-inch-thick slices
- 15 ounces Appenzeller cheese, cut into 1/8-inch-thick slices
Chef Sébastien learned to cook this dish while he was working in a two-Michelin-starred restaurant in Courchevel, France, at a famous ski resort. This authentic French onion soup gratinée has a delicious, fragrant broth and is perfect for cold winter nights.
Technique tip: This recipe is very unique, using whiskey and chicken stock, instead of the more common red wine and beef stock. Make sure that the onions are sautéed fully before adding in the broth. Don't skimp on the cheese! Rich, nutty cheeses such as Gruyère and Appenzeller add much more flavor.
Swap option: This recipe can be made alcohol-free by omitting the alcohol and adding a star anise to the broth as it is cooking, which will give the recipe that tanginess.
Special equipment: Soup crocks.
For the soup:1.
Heat olive oil over medium-high heat in a heavy-bottomed pot.2.
Add in sliced onions and garlic, stirring frequently until beginning to brown.3.
Add butter and bring heat to medium. Stir frequently as butter melts and onions caramelize for 20 minutes. It is key that the onions are well-cooked and have a nice golden color.4.
Deglaze the pot with the whiskey and add the bay leaf and thyme.5.
Add in the chicken stock, stir and cover. Allow to simmer for 30 minutes.6.
Turn off the heat, remove the bay leaf and add an extra splash of whiskey for good measure.
For the gratinée:1.
Preheat broiler to medium-high heat.2.
For individual portions, ladle the hot soup into soup crocks until they are almost full. Allow enough space at the top for the bread to be flush with the top of the bowl. Place 2 slices of baguette over each crock so that the bread fully covers the top (you may need to break up the pieces to do this).3.
Arrange slices of cheese over the top so that the cheese fully covers the bread and also hangs a bit over the sides (for a truly decadent cheese-pull, double up on the cheese — you won't regret it!).4.
Set the soup crocks on a sturdy cookie sheet to catch excess spilling.5.
Place cookie sheet with the prepared soup crocks under the broiler. Watch very closely and allow to brown until the cheese is bubbly on top and beautifully golden. Serve immediately.