Mushroom and Caramelized Onion Soup with Cheesy Toasties Recipe

Introduction

This mushroom and caramelized onion soup is a rich and comforting dish perfect for cozy evenings. It combines deeply caramelized onions with savory mushrooms and is topped with cheesy toasted baguette slices for extra indulgence.

Ingredients

• 4 tablespoons unsalted butter
• 4 large yellow onions, thinly sliced
• 2 cloves garlic, finely chopped
• 2 bay leaves
• 2 sprigs fresh thyme
• 1 cup dry white wine
• 1/4 cup all-purpose flour
• 8 cups beef broth
• Salt and black pepper, to taste
• 1 tablespoon unsalted butter
• 1 tablespoon olive oil
• 1 clove garlic, finely chopped
• 24 ounces cremini mushrooms, quartered
• 1 teaspoon chopped fresh thyme
• 1 baguette, sliced into rounds
• 8 ounces freshly grated Gruyère cheese
• 1/2 cup freshly grated Parmesan cheese, plus more for garnish

Instructions

1. Step 1: Melt 4 tablespoons butter in a large pot over medium heat. Add the sliced onions, bay leaves, thyme, and a pinch of salt.
2. Step 2: Cook the onions slowly, stirring often, for 30 to 40 minutes until they are deeply caramelized.
3. Step 3: Stir in the garlic and cook for 1 minute until fragrant.
4. Step 4: Deglaze the pot with white wine, scraping the bottom to loosen any browned bits. Simmer until the wine is mostly evaporated.
5. Step 5: Sprinkle in the flour, stir well, and cook for 2 minutes to remove the raw flour taste.
6. Step 6: Gradually whisk in the beef broth. Bring the soup to a boil, then reduce the heat and simmer for 20 to 25 minutes.
7. Step 7: Meanwhile, heat 1 tablespoon butter and olive oil in a skillet over medium heat. Add the garlic and sauté for about 30 seconds.
8. Step 8: Add the mushrooms and fresh thyme, cooking for 10 to 12 minutes until the mushrooms are browned. Season with salt and pepper to taste.
9. Step 9: Toast the baguette slices until golden. Top each slice with Gruyère and Parmesan cheese, then broil until the cheese is bubbly and melted.
10. Step 10: Ladle the soup into bowls and top with the cheesy toasties or serve them on the side. Garnish with extra fresh thyme and Parmesan cheese if desired.

Tips & Variations

• Use vegetable broth to make this recipe vegetarian-friendly and substitute the Gruyère with a plant-based cheese for a vegan version.
• Caramelize the onions slowly to develop a deep, sweet flavor that’s key to this soup’s richness.
• For an extra layer of flavor, add a splash of sherry or brandy after deglazing with wine.
• Experiment with different mushroom varieties like shiitake or portobello for varied texture and taste.

Storage

Store the soup in an airtight container in the refrigerator for up to 3 days. Reheat gently on the stove over medium-low heat, stirring occasionally. Keep the cheesy toasties separate and re-toast them briefly before serving to maintain their crispness.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I make this soup ahead of time?

Yes, the soup can be prepared a day in advance. Just reheat it gently before serving and add the cheesy toasties fresh for the best texture.

Can I use a different type of cheese?

Gruyère is classic for its melting qualities and flavor, but you can substitute with Swiss, mozzarella, or a sharp cheddar depending on your preference.

Mushroom and Caramelized Onion Soup with Cheesy Toasties Recipe

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★★★★★

4.9 from 88 reviews

• Author: Simon
• Total Time: 1 hour 35 minutes
• Yield: 6 servings 1x

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Description

This Mushroom and Caramelized Onion Soup with Cheesy Toasties is a comforting and flavorful dish featuring deeply caramelized onions and sautéed cremini mushrooms simmered in a rich beef broth. Topped with golden, cheesy baguette toasties made with Gruyère and Parmesan, this soup is perfect for cozy dinners or special occasions.

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Ingredients

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For the Soup:

• 4 tablespoons unsalted butter
• 4 large yellow onions, thinly sliced
• 2 cloves garlic, finely chopped
• 2 bay leaves
• 2 sprigs fresh thyme
• 1 cup dry white wine
• 1/4 cup all-purpose flour
• 8 cups beef broth
• Salt and black pepper, to taste

For the Mushrooms:

• 1 tablespoon unsalted butter
• 1 tablespoon olive oil
• 1 clove garlic, finely chopped
• 24 ounces cremini mushrooms, quartered
• 1 teaspoon chopped fresh thyme
• Salt and black pepper, to taste

For the Toasties:

• 1 baguette, sliced into rounds
• 8 ounces freshly grated Gruyère cheese
• 1/2 cup freshly grated Parmesan cheese, plus more for garnish

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Instructions

1. Caramelize Onions: Melt 4 tablespoons of butter in a large pot over medium heat. Add the thinly sliced onions, bay leaves, fresh thyme sprigs, and a pinch of salt. Cook slowly, stirring frequently, for 30 to 40 minutes until the onions are deeply caramelized and golden brown.
2. Add Garlic: Stir in 2 cloves of finely chopped garlic and cook for 1 minute until fragrant, being careful not to burn the garlic.
3. Deglaze with Wine: Pour in 1 cup of dry white wine, scraping the bottom of the pot to release any browned bits. Let the wine simmer until mostly evaporated, infusing the onions with depth of flavor.
4. Add Flour: Sprinkle 1/4 cup of all-purpose flour over the mixture, stirring well to combine. Cook for 2 minutes to remove the raw flour taste and help thicken the soup later.
5. Add Broth and Simmer: Gradually whisk in 8 cups of beef broth, ensuring no lumps form. Bring the mixture to a boil, then reduce the heat and let it simmer gently for 20 to 25 minutes to meld the flavors.
6. Sauté Mushrooms: While the soup simmers, heat 1 tablespoon unsalted butter and 1 tablespoon olive oil in a skillet over medium heat. Add 1 clove of finely chopped garlic and sauté for 30 seconds until fragrant. Add the quartered cremini mushrooms and 1 teaspoon chopped fresh thyme. Cook for 10 to 12 minutes, stirring occasionally, until the mushrooms are browned and tender. Season with salt and black pepper to taste.
7. Prepare Toasties: Toast the baguette slices until they are golden brown. Top each slice generously with freshly grated Gruyère cheese and Parmesan cheese. Broil under a hot oven or grill until the cheese is bubbly and lightly browned.
8. Serve: Ladle the hot soup into serving bowls. Stir the sautéed mushrooms into the soup or add on top as desired. Place the cheesy toasties on top of the soup or serve on the side. Garnish with extra Parmesan cheese and fresh thyme sprigs for an elegant finish.

Notes

• For a vegetarian version, use vegetable broth instead of beef broth.
• Be patient while caramelizing onions to develop deep flavor; rushing this step can result in less sweetness and color.
• Use day-old baguette for best toasting results.
• Gruyère is preferred for its melting qualities and nutty flavor, but Swiss cheese can be a substitute.
• Adjust seasoning at the end as broth and cheeses add saltiness.

• Prep Time: 20 minutes
• Cook Time: 1 hour 15 minutes
• Category: Soup
• Method: Stovetop
• Cuisine: French

Keywords: mushroom soup, caramelized onion soup, cheesy toasties, cremini mushrooms, French soup, comfort food, Gruyère cheese