Fleur de Lis French Onion Soup with Crispy Gruyère
A classic French onion soup with slow-simmered caramelized onions, rich broth, and a golden-baked Gruyère topping for an elegant finale. This french-inspired soups ready in about 75 minutes pairs unsalted butter, large, thinly sliced onion, all-purpose flour for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 320 calories and feeds 6, 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
- 3 tbsp unsalted butter
- 4 large, thinly sliced onion
- 2 tbsp all-purpose flour
- 4 cups beef broth
- 1/2 cup dry white wine
- 1 sprig fresh thyme
- 1 bay leaf
- 1/2 tsp salt
- 1/4 tsp black pepper
- 1 cup, grated Gruyère cheese
- 4 slices baguette
Instructions
- Step 1: Melt 3 tbsp unsalted butter in a large pot over medium heat. Add 4 large thinly sliced onions and cook for 25-30 minutes, stirring occasionally, until deeply caramelized and golden brown (low and slow is key).
- Step 2: Sprinkle 2 tbsp all-purpose flour over onions and stir constantly for 1 minute to form a paste, then pour in 1/2 cup dry white wine, scraping up any browned bits from the pot.
- Step 3: Add 4 cups beef broth, 1 sprig fresh thyme, 1 bay leaf, 1/2 tsp salt, and 1/4 tsp black pepper. Bring to a gentle simmer and cook for 20 minutes to develop flavor.
- Step 4: Remove thyme sprig and bay leaf. Ladle soup into oven-safe bowls, then top each with 1/4 cup grated Gruyère cheese and a slice of baguette.
- Step 5: Broil bowls in oven for 2-3 minutes until cheese is melted, bubbly, and golden brown, watching closely to prevent burning.
Equipment for this recipe
Top-rated tools to make this recipe successfully.
Frequently asked questions
How long does Fleur de Lis French Onion Soup with Crispy Gruyère take to make?
Total time is about 75 minutes (20 min prep + 55 min cook). Most home cooks find this fits comfortably into a weeknight; double the batch on Sunday for two dinners.
How do I store leftover Fleur de Lis French Onion Soup with Crispy Gruyère?
Cool to room temperature within 2 hours, then store in an airtight container in the fridge for up to 4 days. Reheat covered in a 350°F oven for 10-12 minutes, or microwave at 70% power in 60-second bursts to keep unsalted butter from drying out.
Can I substitute ingredients in Fleur de Lis French Onion Soup with Crispy Gruyère?
Yes — most ingredients in this recipe have flexible swaps. For oil, use any neutral high-smoke-point oil (avocado, grapeseed, refined coconut). For aromatics, dried herbs at ⅓ the volume of fresh work in a pinch. The full ingredient list is shoppable on Instacart so you can see substitutes in real time.
How do I scale Fleur de Lis French Onion Soup with Crispy Gruyère for a different number of people?
The recipe is written for 6 servings. Multiply each ingredient by (your serving target / 6). Cook time stays roughly the same up to 2x; for 3-4x batches, switch from a skillet to a sheet pan or stockpot so the food isn't crowded — overcrowding steams instead of browns.
What goes well with Fleur de Lis French Onion Soup with Crispy Gruyère?
French soups like this pair well with a simple grain (rice, couscous, or crusty bread), a quick salad with acid (lemon vinaigrette, pickled onions), and a pan sauce or yogurt-based dip. Tap "Plan a meal with the AI" to get specific side suggestions.
What others are saying
- ★★★★☆
Tasty recipe. I'd add a bit more seasoning next time.
- ★★★★☆
Solid recipe. Not groundbreaking but definitely making it again.
- ★★★★☆
Good flavors but the sauce was a bit thin. I'd reduce it longer.
