French Onion Soup

This is one of my favorite fall (treat) soups. I don't make it as often as I think about it, but it is super yummy and easy. I was never a French Onion Soup lover until Candler took me to La Chatelaine back when we were dating. So yummy and this is just as good!

French Onion Soup
Source - America's Test Kitchen Family Cookbook
Serves - 8 (I would say 4 main dish servings)
Prep Time - 15 min    Total Time - 1 hour 10 min

This soup requires oven safe bowls because the cheese is browned directly on top of the soup. The best choice is a small deep, bowl so that the cheese and bread completely cover the top of the soup.

1 T unsalted butter
5 medium red onions (about 3 pounds), halved and thinly sliced
2 t minced fresh thyme or 1/2 t dried
Salt
1/4 C balsamic vinegar
6 cups chicken broth
1 3/4 cups beef broth (one can)
2 bay leaves
Pepper
1 baguette thinly sliced 1/2 inch thick (I would say we used 1/2 a loaf total)
8 oz (2 C) Swiss cheese, shredded (I have also subbed mozzarella and it was still yummy)

1. Melt the butter in a large Dutch oven over medium heat. Add the onions, thyme, and 1/2 t salt. Cook, stirring occasionally, until the onions are dark and sticky, about 30 minutes.

2. Stir in the balsamic vinegar and scrape the browned crust from the pot. Stir in the chicken broth, beef broth, and bay leaves. Bring to a simmer and cook for 20 minutes. Season with salt and pepper to taste and discard the bay leaves.

3. Adjust an oven rack to the middle position and heat the oven to 450 degrees. Arrange oven safe bowls on a rimmed baking sheet and ladle the soup into them. Top each bowl with 2 baguette slices and sprinkle each with 1/4 cup of the cheese. Bake until the cheese has melted, about 5 minutes. Serve hot.

To Make Ahead or Freeze:
This soup can be prepared through step 2, cooled, covered and refrigerated for up to 2 days or frozen for up to 1 month. Reheat over low heat and proceed with step 3.