This version of French onion soup takes time but the results are worth it.
AuthorLemons & Anchovies
5very large onions (I used Walla Walla), sliced
Several sprigs of fresh thymetied together with kitchen twine
4 - 6cupsbeef broth
2 - 4cupswateror half water and half chicken stock + extra for breaking up the fond
(You will need a large stock pot or dutch oven to accommodate the onions for this recipe.)
Heat the olive oil over medium heat then add the onions and a pinch or two of salt. You may have to add the onions in batches. Once the initial batch begins to cook down, you can add the rest. Cook, stirring occasionally for 1- 1 1/2 hours. The onions will release their liquid so they will get watered down a lot--this is to be expected. You can turn up the heat to medium-high to help the liquid dissolve sooner but you can expect this part to take about 20 minutes. Once the liquid has evaporated the onions will begin to brown and caramelize--this is the fond. As the fond develops at the bottom of the pot, stir the onions to prevent burning. You can also add a splash or two of water to help release the fond (I only did this once or twice). Reduce the heat to medium if the onions are browning too quickly. You will need to follow this step of releasing the fond and stirring the onions a few times over the course of 1- 1 1/2 hours. Note: Taste as you go. You may not need all this time if your onions have developed enough flavor. Walla Walla onions contain a bit more sugar than regular onions so consider this when trying out the recipe; it may take a little less or more time for you.
Once the onions are uniformly brown and flavorful add the thyme, bay leaf, 4 cups of beef stock and 2 cups of water (or chicken stock if using). Bring to a boil then simmer for about 15 minutes. Taste the soup. Because of the natural sweetness of the Walla Walla onions I found mine to be a bit rich (and also with 4 cups of broth and 2 cups of water the onion to liquid ratio was a bit high for me) so I added more stock and water as I heated up leftovers (you can add it all at once, too). If you like a higher onion to liquid ratio you may not need to add the remaining liquid.
Ladle some of the soup in oven-safe bowls. Turn on your broiler and place a slice or two of sliced baguette topped with gruyere slices. Set the bowls on a baking tray and broil the soup until the cheese has melted and starts to turn golden. Serve immediately. This soup will keep for a few days in the refrigerator.