I hated French onion soup from high school until only a couple years ago, probably because my only experience with it was the high school cafeteria version of it – overly salty, with a slight tinny tang from the soup cans, and a sad island of soggy bread floating on top. Gross.

So I never tried it again until my husband told me that he loved French onion soup and that he’d like me to make it sometime. I was skeptical, but I turned to the good folks at America’s Test Kitchen because if anyone can do French onion soup well, they can. My America’s Test Kitchen Family Cook Book and Family Baking Book have become my go-to resources for  solving any culinary trickiness. Overwhelmed at the prospect of making chicken cordon bleu? Their recipe is killer. Want a no-fail recipe for amazing buttermilk drop biscuits? Their recipe is perfection. So I whipped up the America’s Test Kitchen recipe for French onion soup and of course, it is awesome.

This is amazing soup. It is savory and bursting with flavor from the sweet red onions that are cooked down to mellow deliciousness, from the fresh thyme, and from the surprise (to me at least) ingredient of balsamic vinegar, which adds a wonderful richness and complexity to the dish. The geniuses at America’s Test Kitchen noted that many French onion soup recipes have a tinny flavor from the beef broth, and their solution works wonderfully: the recipe calls mostly for chicken broth, with just enough beef broth for flavor without giving the soup a strange aftertaste. (I use Swanson Natural Goodness chicken broth, which is lower in salt and has no MSG. For the beef broth, I used Rachel Ray’s brand, because that is the only kind I could find in the store that does not use MSG.) The results are French onion soup perfection – savory and deeply flavorful and satisfying. This is ultimate comfort food.

So if you’ve been haunted by memories of bad, bad French onion soup, don’t let that stop you from making this. French onion soup, it turns out, is actually amazingly delicious – as long as you have the right recipe!

French Onion Soup

From America’s Test Kitchen Family Cook Book

Serves 8

Prep time: 15 minutes Total Time: 1 hour 10 minutes

2 tablespoons unsalted butter

5 medium red onions (about 3 pounds), halved and sliced thin

2 teaspoons minced fresh thyme, or 1/2 teaspoon dried


1/4 cup balsamic vinegar

6 cups low-sodium chicken broth

1 3/4 cups low-sodium beef broth

2 bay leaves


1 baguette, sliced 1/2 inch thick

8 ounces Swiss cheese, shredded (2 cups)

  1. Melt the butter in a large Dutch oven over medium heat. Add the onions, thyme, and 1/2 teaspoon salt. Cook, stirring occasionally, until the onions are translucent, dark and sticky, about 30 minutes.
  2. Stir in the vinegar and deglaze the pan, scraping all the delicious browned bits from the bottom of 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 soup 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.

To make ahead: This soup can be prepared through step 2, cooled, covered, and refrigerated for up to 2 days or frozen up to 1 month. Reheat over low heat and proceed with step 3. (We ate it over a period of about 5 days and it tasted delicious every time.)