This putzy, Cook’s Illustrated recipe still makes the best French onion soup, hands down. To break up the time commitment a bit, I caramelize the onions in the oven the first night and then finish the soup in about 2 hours on the stove top the next night.
3 tablespoons butter
6 large yellow onions (about 4 pounds)
2 – 3 cups water
1/2 cup dry sherry or red wine
4 cups chicken broth (Pacific Natural)
2 cups beef broth (Pacific Natural)
1 teaspoon dried thyme
1 bay leaf
Ground black pepper
Heat oven to 400°F and adjust the rack to the lower-middle position.
Halve the onions and cut pole to pole into 1/4-inch-thick slices. Try to stick with yellow onions as this dish needs their lower sugar and stronger, more complex flavor.
Grease a large Dutch oven and add the butter, onions, and salt. Put in the oven and cook, covered, for 1 hour. Remove the pot from the oven and stir the onions, making sure to scape the bottom and sides. Return the pot to the oven with the lid slightly ajar and cook for another hour. Again, remove the pot and give everything a good stir. Return the pot to the oven with the lid slightly ajar continue to cook until the onions are very soft and golden brown (about 30 to 45 minutes).
Remove the pot from the oven. At this point you can let the onions cool in the pot and refrigerate for a day or so before continuing with the recipe.
Move the pot to the stove top over medium-high heat. Continue cooking the onions, stirring frequently and scraping bottom and sides of pot, until all the liquid evaporates and the onions brown (about 15 to 20 minutes).
Reduce the heat to medium and continue to cook, stirring frequently, until the pot bottom is coated with a dark crust of fond (about 6 to 8 minutes). Scrape the tasty brown goodness back into onions.
Deglaze the pot with 1/4 cup water, scraping the pot bottom to loosen crust, and cook until the water evaporates and pot bottom has formed yet another dark crust (another 6 to 8 minutes).
Add another 1/4 cup of water and deglaze the pot again, cooking until the water evaporates and pot bottom has formed yet another dark crust (another 6 to 8 minutes).
One more time – add another 1/4 cup of water and deglaze yet again, cooking until the water has evaporated and the onions are very dark brown.
Now (big change of pace here) stir in the sherry and cook, stirring frequently, until the sherry evaporates (about 5 minutes).
Stir in all the the broths, 2 cups of water, thyme, bay leaf, and 1/2 teaspoon salt, scraping up any remaining bits of browned crust on bottom and sides of pot.
Increase heat to high and bring to simmer. Reduce the heat to low, cover, and simmer for 30 minutes. Discard the bay leaf and adjust the seasoning with salt and pepper.
I served this steaming hot with a sprinkling of Gruyère cheese and lots of bread for dipping.
Excellent soup – nice clean onion flavor, but with a a lot of depth and richness to it. It was a real winner both as a dinner served along with grilled ham and cheese sandwiches, and as a warming lunch after a round of shoveling snow.