Food & Cooking Recipes Soups, Stews & Stocks Soup Recipes Freezable French Onion Soup 2.9 (83) 21 Reviews By Martha Stewart Test Kitchen Martha Stewart Test Kitchen The recipes developed by our test kitchen team have undergone a rigorous process of development and testing, ensuring that every element is optimal, from ingredient amounts to method and cooking time. This process includes triple-testing recipes to ensure they meet our high standards. The many stellar cooks and food editors who have been part of our team include Sarah Carey, Lucinda Scala Quinn, Jennifer Aaronson, Shira Bocar, Anna Kovel, Greg Lofts, Riley Wofford, Lauren Tyrell, and Lindsay Leopold. Editorial Guidelines Updated on February 1, 2023 Print Rate It Share Share Tweet Pin Email Prep Time: 20 mins Total Time: 2 hrs Servings: 8 It takes time to caramelize the onions, but it's well worth the effort for the depth of flavor they bring to this French onion soup. Serve it in deep bowls and top with savory cheese toast for a rich soup worthy of any Parisian bistro. Make ahead and freeze for up to three months to enjoy French onion soup any time. Ingredients 10 medium yellow onions (about 4 ½ pounds), halved, peeled, and thinly sliced 2 tablespoons olive oil 2 tablespoons sugar 1 teaspoon dried thyme Coarse salt and ground pepper 3 cans (14 ½ ounces each) reduced-sodium chicken broth ¾ cup dry red wine For Cheese Toast (Optional) 4 slices toasted multigrain bread 4 ounces sliced Swiss cheese Directions Preheat oven to 450 degrees. In a large roasting pan, toss together onions, oil, sugar, thyme, 2 teaspoons salt, and 1/4 teaspoon pepper. Cover tightly with foil; cook until steamed, about 30 minutes. Uncover; cook, stirring every 30 minutes, until onions are golden brown and caramelized, 1 to 1 1/4 hours more. Transfer onion mixture to a large saucepan (reserve roasting pan); stir in broth and 6 cups water. Bring to a boil; reduce heat to a simmer. Cook until liquid has darkened, about 20 minutes. Meanwhile, deglaze the roasting pan with wine: Place the pan over medium heat; add wine. Scrape bottom of pan with a wooden spoon or scraper to loosen any browned bits. Simmer until reduced and syrupy, about 2 minutes. Pour liquid (and browned bits) into soup. Season with salt and pepper. (If freezing, let cool completely before transferring to airtight containers, leaving 1 inch at top.) If desired, make the cheese toast: Heat broiler. Place bread on a baking sheet; top with Swiss cheese. Broil until cheese is bubbly and golden brown, 2 to 3 minutes. Cut each slice into four triangles. To serve, divide soup among bowls; garnish each with two triangles of cheese toast, if desired. Cook's Notes To cut onion slices, halve through the root end; peel back skin. Place halves, cut sides down, on cutting board. Trim both ends; thinly slice onion lengthwise. To slice onions quickly, use a food processor fitted with a slicing blade (instead of a knife). This soup can be frozen for up to three months; to serve, defrost, and warm on the stove, over low heat. Rate it Print