Sautéed Mushroom and Thyme Soup with Parmesan Croutons

By AislePrompt Editorial · Published 2026-05-01 · Updated 2026-05-01

An earthy mushroom soup enriched with fresh thyme and topped with crispy Parmesan croutons for an elegant starter or light meal. This French-inspired soup recipe (vegetarian), ready in about 45 minutes, pairs cremini mushrooms, yellow onion, garlic cloves 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

• 12 oz, sliced cremini mushrooms
• 1 medium, diced yellow onion
• 3 cloves, minced garlic cloves
• 3 tbsp unsalted butter
• 2 tbsp all-purpose flour
• 4 cups vegetable broth
• 1 tbsp fresh thyme leaves
• 1/2 cup heavy cream
• 1 tsp salt
• 1/2 tsp black pepper
• 6 baguette slices
• 1/2 cup grated Parmesan cheese
• 2 tbsp olive oil

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Instructions

1. Step 1: Melt 3 tbsp unsalted butter in a large pot over medium heat. Add 1 medium diced yellow onion and sauté for 5 minutes until softened. Add 3 cloves minced garlic and cook for 1 minute until fragrant.
2. Step 2: Add 12 oz sliced cremini mushrooms and 1 tbsp fresh thyme leaves. Sauté for 10 minutes, stirring occasionally, until mushrooms release their liquid and become golden brown.
3. Step 3: Sprinkle 2 tbsp all-purpose flour over the mushrooms and stir well to coat. Cook for 2 minutes to remove raw flour taste.
4. Step 4: Gradually pour in 4 cups vegetable broth, stirring constantly to prevent lumps. Bring to a simmer and cook for 15 minutes until soup thickens slightly.
5. Step 5: Meanwhile, preheat oven to 375°F. Arrange 6 baguette slices on a baking sheet. Brush each slice with 2 tbsp olive oil and sprinkle evenly with 1/2 cup grated Parmesan cheese. Bake for 8-10 minutes until golden and crispy.
6. Step 6: Stir 1/2 cup heavy cream into the soup and season with 1 tsp salt and 1/2 tsp black pepper. Heat through but do not boil.
7. Step 7: Serve soup hot, garnished with Parmesan croutons on top for crunch.