Slow-Simmered French Onion Soup
A classic French comfort food featuring deeply caramelized onions simmered in rich broth, topped with a golden crust of melted Gruyère cheese. This French-inspired soup recipe, ready in about 90 minutes, pairs yellow onion, unsalted butter, all-purpose flour for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 350 calories and feeds 4, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.
Ingredients
- 700 grams yellow onion
- 2 tablespoons unsalted butter
- 1 tablespoon all-purpose flour
- 4 cups beef broth
- 120 milliliters dry white wine
- 50 grams Gruyère cheese
- 4 slices baguette
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Instructions
- Step 1: Thinly slice 700 grams yellow onions and cook in 2 tablespoons unsalted butter over medium-low heat for 45-50 minutes until deeply golden brown, stirring occasionally to prevent burning.
- Step 2: Sprinkle 1 tablespoon all-purpose flour over onions, stir to coat, and cook for 1 minute.
- Step 3: Pour in 120 milliliters dry white wine, simmer for 5 minutes to evaporate alcohol, then add 4 cups beef broth and simmer uncovered for 20 minutes.
- Step 4: Ladle soup into oven-safe bowls, top each with 50 grams grated Gruyère cheese, and broil under high heat for 2-3 minutes until golden.
