Slow-Caramelized Onion Soup with Thyme

By AislePrompt Editorial · ·

How this recipe was made — this recipe was drafted by AislePrompt's AI-assisted pipeline from technique templates and USDA-sourced nutrition data, and published by AislePrompt Editorial — see how AislePrompt recipes are developed and reviewed.

Deeply sweet onions simmered for hours until golden-brown, layered with a herb-infused broth and toasted baguette slices for a classic French comfort dish. This French-inspired soup recipe, ready in about 85 minutes, pairs yellow onions, unsalted butter, chicken stock 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.

Prep: 20 min Cook: 65 min Serves 6 French cuisine 320 cal/serving
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Ingredients

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Instructions

  1. Step 1: Melt 3 tablespoons unsalted butter in a heavy-bottomed pot over medium heat, add 2 pounds thinly sliced yellow onions, and cook uncovered for 45 minutes, stirring every 10 minutes until deeply golden brown and caramelized.
  2. Step 2: Pour in 4 cups chicken stock and add 2 sprigs fresh thyme, then simmer gently for 20 minutes to meld flavors while reducing slightly.
  3. Step 3: Remove thyme sprigs and blend the soup until smooth using an immersion blender, or carefully transfer to a regular blender in batches.
  4. Step 4: Preheat oven broiler to high. Place 1 slice baguette on a baking sheet and top with 1/4 cup grated gruyere cheese.
  5. Step 5: Broil 4 inches from heat for 2-3 minutes until cheese bubbles and turns golden, then place on top of soup bowls.

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