I encountered this Onion Soup recipe in a DVD by America's Test Kitchen.
Three pounds of sliced onions on the left. Onions cooking down on the right.
French Onion Soup Gratinee
Tie the parsley and thyme sprigs together with kitchen twine so they will be easy to retrieve from the soup pot. Slicing the baguette on the bias will yield slices shaped to fill the mouths of the bowls.
Serves 6 (more at my house)
2 tablespoons unsalted butter
5 medium red onions (about 3 pounds), sliced thin
Table salt
6 cups low-sodium chicken broth (canned)
1 3/4 cups low-sodium beef broth (canned)
1/4 cup dry red wine
2 sprigs fresh parsley leaves
1 sprig fresh thyme leaves
1 bay leaf
1 tablespoon balsamic vinegar
Ground black pepper
1 baguette , cut on the bias into 3/4-inch slices (2 slices per serving)
4 1/2 ounces Swiss cheese , sliced 1/16-inch thick
1 1/2 ounces grated Asiago cheese (about 3/4 cup)
1. Melt butter in large soup kettle or Dutch oven over medium-high heat; add sliced onions and 1/2 teaspoon salt and stir to coat onions thoroughly with butter. Cook, stirring frequently, until onions are reduced and syrupy and inside of pot is coated with very deep brown crust, 30 to 35 minutes. Stir in the chicken and beef broths, red wine, parsley, thyme, and bay leaf, scraping pot bottom with wooden spoon to loosen browned bits, and bring to simmer. Simmer to blend flavors, about 20 minutes, and discard herbs. Stir in balsamic vinegar and adjust seasonings with salt and pepper. (Can be cooled to room temperature and refrigerated in airtight container up to 2 days; return to simmer before finishing soup with croutons and cheese).
2. For the Crusts: Adjust an oven rack to the upper-middle position and heat the oven to 350 degrees. Spread the bread out on a rimmed baking sheet and bake, flipping once, until lightly browned, about 15 minutes. Remove the bread from the oven. Turn the oven to broil.
3. Set heat-safe soup bowls or crocks on rimmed baking sheet and fill each with about 1 1/2 cups soup. Top each bowl with two toasted baguette slices and divide Swiss cheese slices, laying them in a single layer, if possible, on bread. Sprinkle each serving with about 2 tablespoons grated Asiago cheese and broil until well browned and bubbly, 7 to 10 minutes. Cool 5 minutes and serve.Here are the pictures of 3 lbs. of onions, sliced ($1.99 at Trader Joe) then the red onions cooking down, a very important view of the brown crust, which really does take over half an hour to form and a final picture of the rich brown finished soup. I didn't take one of the bowls ready to serve. We ate them up in about 10 minutes.
Look to the next post for more pictures.
This is the all-important rich brown crust that develops after caramelizing the onions.
