This Mushroom Croissant Filling is the ultimate savory stuffing made from scratch with a decadent blend of earthy mushrooms and melted Gruyère. It transforms simple croissants into an elegant meal in just 50 minutes total time. This luxurious filling is perfect for brunch gatherings or a comforting weeknight supper, bringing restaurant quality to your kitchen.

I discovered my love for rich, savory fillings while tasting my way through French bakeries, where the scent of butter and mushrooms is a morning ritual. This recipe captures that essence, a creamy mushroom filling I now make for cozy weekend brunches or to impress guests. It pairs beautifully with a simple green salad and my cheesy garlic bliss bread for a complete, satisfying meal.

On crisp autumn mornings, I love serving these alongside a warm bowl of stracciatella soup for the ultimate comfort food experience. The recipe is wonderfully adaptable, allowing you to create something truly special with minimal effort.

Four Reasons This Mushroom Filling Will Become a Staple

• Restaurant Quality at Home: The combination of Gruyère and fresh thyme creates a sophisticated flavor profile.
• Quick and Simple: Ready in under an hour, with most of the time being hands off.
li>Incredibly Versatile: Perfect for croissants, but also wonderful in pastries or as a topping.
• Make Ahead Convenience: The filling can be prepared a day in advance, making assembly a breeze.

Gather Your Mushroom Croissant Filling Ingredients

Be sure to see the recipe card below for the full listing of ingredients, instructions, notes, and estimated nutritional information.

Mushroom Croissant Filling

Make this creamy Mushroom Croissant Filling with Gruyère and cream cheese. Perfect for savory pastries.

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Prep Time 15 minutes mins

Cook Time 20 minutes mins

15 minutes mins

Total Time 50 minutes mins

Course Appetizer, Snack

Cuisine French-Inspired

Servings 6 servings

Calories 180 kcal

Equipment

• large skillet or Dutch oven
• cutting board
• knife
• measuring spoons
• measuring cups
• spatula

Ingredients

  

• 1 pound mixed mushrooms, such as cremini and shiitake, cleaned and thinly sliced
• 2 tablespoons unsalted butter
• 1/2 cup yellow onion, finely chopped
• 2 cloves garlic, minced
• 1 tablespoon all-purpose flour
• 1/4 cup heavy cream
• 2 ounces cream cheese, softened and full-fat
• 1/2 cup Gruyère cheese, shredded
• 1 teaspoon fresh thyme, chopped
• 2 tablespoons fresh parsley, finely chopped
• 1/2 teaspoon kosher salt, plus more to taste
• 1/4 teaspoon freshly ground black pepper, plus more to taste

Instructions

 

• Heat a large, heavy-bottomed skillet or Dutch oven over medium-high heat. Add the unsalted butter and allow it to melt completely. Add the sliced mushrooms to the skillet and cook, stirring occasionally, for 8 to 10 minutes, until they have released their liquid and are nicely browned and tender.
• Reduce the heat to medium. Add the finely chopped yellow onion to the skillet with the mushrooms and cook for 3 to 4 minutes, stirring frequently, until the onion softens and becomes translucent.
• Stir in the minced garlic and chopped fresh thyme. Cook for an additional 1 minute, stirring constantly, until fragrant. Be careful not to burn the garlic.
• Sprinkle the all-purpose flour over the mushroom mixture and cook for 1 minute, stirring well to ensure the flour coats everything and cooks out any raw flour taste.
• Gradually pour in the heavy cream, stirring constantly. Bring the mixture to a gentle simmer and cook for 2 to 3 minutes, stirring occasionally, until the sauce thickens slightly.
• Remove the skillet from the heat. Stir in the softened cream cheese and shredded Gruyère cheese until both cheeses are fully melted and smoothly incorporated into the filling.
• Add the finely chopped fresh parsley, 1/2 teaspoon of kosher salt, and 1/4 teaspoon of freshly ground black pepper. Taste the filling and adjust seasonings as needed, adding more salt or pepper to your preference. Allow the filling to cool for at least 15 minutes before using it to fill croissants.

Notes

Allow the filling to cool completely before using it to fill croissants.

Keyword croissant, mushroom, savory filling

Creative Ways to Customize Your Filling

• Add Protein: Stir in about a cup of diced, cooked ham or crispy bacon for a heartier version.
• Herb Swap: Try using fresh tarragon or rosemary instead of thyme for a different aromatic profile.
• Extra Cheesy: Add a tablespoon of grated Parmesan along with the Gruyère for a sharper flavor.

My Pro Tips for Perfect Mushroom Filling

• Proper Sautéing: Let the mushrooms cook undisturbed for a few minutes to achieve a good sear and deepen their flavor.
• Roux Consistency: Cook the flour for a full minute to remove the raw taste but avoid burning it.
• Cheese Incorporation: Remove the skillet from heat before adding the cheeses to prevent them from becoming grainy.
• Cooling is Key: Let the filling cool completely so it thickens and is easier to handle when stuffing croissants.

How to Store and Reheat Your Filling

• Store: Keep the cooled filling in an airtight container in the refrigerator for up to 3 days.
• Freeze: For longer storage, freeze in a freezer safe container for up to 2 months. Thaw overnight in the fridge.
• Reheat: Warm gently in a saucepan over low heat, stirring often, or in the microwave in 30 second intervals.
• Make Ahead Tip: You can prepare the entire filling a day ahead, making it perfect for effortless entertaining or a quick brunch spread.

Frequently Asked Questions

More Savory Recipes You’ll Adore

• Chicken Pot Pie
• Spinach Manicotti
• Stuffed Bell Peppers
• Swiss Mushroom Burger

Why This Mushroom Croissant Filling Earns Rave Reviews

With its rich, creamy texture and deeply savory flavor, this Mushroom Croissant Filling turns a simple pastry into a memorable meal. It is surprisingly straightforward to make from scratch, yet the result feels decadent and special. I hope this recipe brings as much comfort and joy to your table as it has to mine.