- 2 pounds onions, sliced very thinly,
- 1/8-1/4 inch.
- 3 tablespoons butter,
- plus extra for buttering the bread
- 2 oz Calvados (brandy or cognac may be used as a substitute)
- 6 cups homemade chicken stock
- 2 bay leaves
- 5 sprigs thyme
- 10 oz Gruyere cheese, grated
- salt and pepper, to taste
To start, sweat the onions very, very slowly over low heat. This allows all the natural sugars to caramelize and helps the soup develop a more hearty, robust flavor. Don’t rush this process!
The onions will need up to a full hour and a half in order to cook properly. Give them an occasional stir. Meanwhile, have a pot of stock heating on the stove so that when it comes time for use, it will be warm and ready to go.
Once the onions have turned a deep golden brown, deglaze the pan with Calvados. Be sure to scrape up all the good bits that are sticking to the bottom of the pan. Simmer for a few minutes to cook off the alcohol.
Add the chicken stock, bay leaves and thyme. Simmer for 35-40 minutes.
While the soup is simmering, prepare the toasts. Preheat the oven to 350. Slice the baguette into 3/4 inch slices and lay on a baking tray. Spread butter on one side of the bread and toast in the oven until crispy and golden, about 8 minutes. Set aside.
Turn on the broiler to high.
Once the soup has simmered, season with salt and pepper. Ladle the soup into the gratin dishes, top with two overlapping toasts, and sprinkle generously with Gruyere. Place under the broiler and cook until the cheese is melted and bubbly, about 3 minutes. This happens quickly, so be sure not to burn your toasts!
*The yield for this recipe will vary depending on the size of your gratin dishes. Ours were tremendous and this recipe only yielded two portions. However, this recipe should easily serve four if baked in smaller ramekins. The ratio of ingredients will remain the same, just be sure to prepare two toasts for each ramekin and portion the cheese equally among the baking dishes. Snack on any cheese that might be leftover.