Just one bite of this cheesy, crunchy crostini-topped French Onion Soup makes every minute of caramelizing the onions well worth it.
French Onion Soup
Serves: Makes about 2 quarts
- 5 tablespoons unsalted butter
- 2 pounds Vidalia or other sweet onions, thinly sliced
- 1 pound red onions, thinly sliced
- 1 teaspoon kosher salt
- ½ teaspoon sugar
- ½ teaspoon ground black pepper
- 6 cups low-sodium beef broth
- 2 tablespoons sherry vinegar
- 10 sprigs fresh thyme
- 2 dried bay leaves
- 6 (1-inch-thick) slices baguette
- 1 cup shredded sharp white Cheddar cheese
- Garnish: chopped fresh thyme, ground black pepper
- In a large Dutch oven, melt butter over medium-high heat. Add all onions; cook, stirring occasionally, until softened, about 15 minutes. Reduce heat to medium. Stir in salt, sugar, and pepper; cook, stirring occasionally, until onions are golden brown, about 50 minutes. Gradually stir in broth and vinegar, scraping bottom of pot with a wooden spoon.
- Tie thyme sprigs and bay leaves together with kitchen string; add to pot, and bring to a boil. Reduce heat to medium-low; cook until soup is slightly thickened, about 30 minutes. Discard herb bundle.
- Preheat oven to broil. Place 6 (1-cup) broiler-safe ramekins on a baking sheet.
- Ladle soup into ramekins. Top each with a baguette slice; sprinkle with cheese.
- Broil until cheese is golden brown, about 3 minutes. Garnish with thyme and pepper, if desired. Serve immediately.
This soup freezes well. Let cool completely, and then freeze in 1-quart portions for up to 3 months. Be sure to label and date the package.