Name: Mushroom Tart with Gruyere and Thyme Recipe
Prep time: 30 min
Cook time: 30 min
Total time: 1 h
Cuisine: French
Ingredients: 175 grams (1½ cup plus 1 tablespoon) all-purpose flour; ¼ teaspoon salt; 113 grams (1 stick) cold butter, cut into 1-2 inch cubes; 2-3 tablespoons cold water; 1 pound mushrooms, sliced (any type); 1-2 teaspoons olive oil or butter; ¼ teaspoon salt; ¼ teaspoon garlic powder; ¼ teaspoon black pepper; 3 sprigs fresh thyme (or ½ teaspoon dried thyme); ½ cup heavy cream; 1 large egg; ½ cup shredded Gruyere or mozzarella cheese

Jump to Recipe· 3.9 from 62 reviews

If you’ve been searching for a delightful dish that brings together earthy mushrooms, creamy Gruyere, and aromatic thyme, then you have to try this Mushroom Tart with Gruyere and Thyme Recipe. It’s a perfect balance of buttery, flaky crust and a luscious filling that’s both rich and comforting. Whether for a cozy family dinner or to impress friends at a brunch, this tart offers an irresistible combination of flavors and textures that’ll quickly become one of your go-to savory treats.

Ingredients You’ll Need

The image shows an arrangement of cooking ingredients on a white marbled surface. There is one container with fresh white mushrooms placed in the center bottom, a round white bowl to the right filled with white flour and a spoon inside it, and a rectangular white plate with a thick stick of yellow butter below. To the left, a white square plate holds a single brown egg and green thyme sprigs. Above the mushrooms, a round white bowl is filled with shredded orange cheese. Three small white bowls hold different ingredients: one with light brown and white seasonings above the mushrooms, one with white salt to the right of the butter, and one with clear water above the salt. Lastly, a white rectangular box of heavy cream is partially visible at the bottom left. Photo taken with an iphone --ar 4:5 --v 7

The beauty of this Mushroom Tart with Gruyere and Thyme Recipe lies in its simplicity—the ingredients are simple, yet each one plays a crucial role in creating layers of flavor and texture you’ll love. From the flaky crust to the tender mushrooms and creamy custard, every component is essential.

All-purpose flour (175 grams or 1½ cup plus 1 tablespoon): This forms the tender, buttery crust that holds everything together perfectly.

Salt (¼ teaspoon): Enhances the flavors in the dough and filling without overwhelming the delicate mushroom taste.
Cold butter (113 grams or 1 stick): Creates the flaky texture in the pâte brisée crust; keep it chilled for best results.
Cold water (2-3 tablespoons): Gently brings the dough together without making it tough.

Sliced mushrooms (1 pound): Choose your favorite variety or mix them for a deeper flavor; mushrooms lend an earthy richness.
Olive oil or butter (1-2 teaspoons): For sautéing the mushrooms and infusing them with a luscious, golden finish.
Salt, garlic powder, and black pepper (¼ teaspoon each): Season the mushrooms delicately to enhance their natural umami.

Fresh thyme sprigs (3 sprigs) or dried thyme (½ teaspoon): Adds an aromatic herbal note that complements the mushrooms stunningly.
Heavy cream (½ cup): Ensures a silky, rich custard that binds the filling smoothly.
Large egg (1): Helps set the custard and adds a lovely richness to the filling.

Shredded Gruyere or mozzarella cheese (½ cup): Gruyere gives a nutty, slightly sweet flavor, while mozzarella keeps it mild and melty.

How to Make Mushroom Tart with Gruyere and Thyme Recipe

Step 1: Prepare the Pâte Brisée Crust

Begin by mixing the flour and ¼ teaspoon salt in a large bowl. Add the cold butter cubes and use your fingers to rub it into the flour until the mixture looks like coarse crumbs with some pea-sized bits of butter remaining. This technique is key to achieving that flaky, buttery layer we all love in a tart crust. Slowly add cold water, one tablespoon at a time, mixing gently until the dough just comes together. Don’t overwork it—brief kneading is perfect!

Step 2: Chill the Dough

Form the dough into a flat disk, wrap it tightly in plastic wrap, and pop it into the fridge for at least 30 minutes. This chilling step lets the flour hydrate fully and keeps the butter cold, essential for a crisp crust.

Step 3: Roll Out and Blind Bake the Crust

Lightly grease a 9-inch tart pan with butter. On a floured surface, roll out the dough into a large thin circle and carefully transfer it to the tart pan. Trim any excess dough and prick the bottom lightly with a fork. Return it to the fridge for 15 minutes to rest and chill further. Then, preheat your oven to 350℉. Line the crust with parchment paper and fill with pie weights, dried beans, rice, or even sugar for blind baking. Bake for 15 minutes, then remove the weights and parchment and bake another 5 to 7 minutes until the crust is lightly golden. Let it cool while you prepare the filling.

Step 4: Sauté the Mushrooms

Heat 1-2 teaspoons of olive oil or butter in a large skillet over medium heat. Add the sliced mushrooms and cook until their moisture evaporates and they start browning nicely—this step releases their deep, umami flavors. Season with ¼ teaspoon each of salt, garlic powder, and black pepper. Toss in fresh thyme and cook for an additional 2 minutes before removing from heat. Allow the mushrooms to cool slightly before moving on.

Step 5: Make the Custard Filling

In a small bowl, whisk together the heavy cream and egg until fully combined. This rich custard will pour over the mushrooms to create that silky filling we crave.

Step 6: Assemble and Bake the Tart

Preheat your oven again to 350℉. Place the sautéed mushrooms into the cooled tart shell, reserving a few slices for the top to create a decorative finish. Pour the cream and egg mixture evenly over the mushrooms. Sprinkle the shredded Gruyere cheese over the top, then arrange the reserved mushroom slices and extra thyme sprigs if you like. Bake the tart for about 20 minutes, or until the cheese melts beautifully and the custard sets firmly. Let the tart cool a bit before slicing.

How to Serve Mushroom Tart with Gruyere and Thyme Recipe

A close-up of a slice of savory pie on a white marbled surface, showing three layers: a crispy, golden-brown crust at the bottom with flaky edges, a middle layer filled with cooked mushrooms and herbs mixed in a light egg base, and a top layer covered in melted golden-yellow cheese with green herb sprigs sprinkled on top. Small crumbs from the crust are scattered around the slice. Photo taken with an iphone --ar 4:5 --v 7

Garnishes

Add a sprinkle of freshly chopped thyme or a light dusting of freshly ground black pepper to elevate the look and flavor just before serving. For a pop of color, a handful of microgreens or thinly sliced scallions provides a fresh contrast to the rich tart.

Side Dishes

This tart pairs wonderfully with a crisp green salad dressed in lemon vinaigrette to cut through the richness. Roasted baby potatoes or a simple bowl of tomato soup can turn it into a hearty meal. The earthy notes of the mushrooms work beautifully alongside bright, fresh vegetables and lighter sides.

Creative Ways to Present

Try serving the Mushroom Tart with Gruyere and Thyme Recipe cut into small squares as savory finger food at your next gathering. You can even prepare mini tarts using muffin tins for individual servings. Another fun idea is to drizzle a little truffle oil over the finished tart to enhance the mushroom flavor and add a luxurious touch.

Make Ahead and Storage

Storing Leftovers

Leftover tart keeps well covered in the refrigerator for up to 3 days. Store it in an airtight container or wrapped tightly with plastic wrap to maintain freshness and prevent the crust from becoming soggy.

Freezing

If you want to keep the tart longer, wrap it tightly in aluminum foil and freeze for up to one month. Thaw overnight in the refrigerator before reheating for the best texture.

Reheating

To enjoy the tart warm, reheat it in a preheated oven at 350℉ for 10-15 minutes or until the filling is heated through and the crust is crisp again. Avoid microwaving if possible to keep the crust flaky and delicious.

FAQs

Can I use other types of mushrooms for this tart?

Absolutely! While button or cremini mushrooms work well, mixing in shiitake, oyster, or portobello mushrooms can add complexity and more depth to the flavor.

Is it possible to make this tart vegetarian or vegan?

This recipe is vegetarian as long as you use vegetarian cheese. For a vegan version, you would need to substitute the butter with plant-based fats, use a vegan cheese alternative, and replace the egg and cream with suitable vegan custard substitutes.

What can I substitute if I don’t have Gruyere cheese?

Mozzarella is a great milder alternative, but you can also experiment with other melting cheeses like Fontina or Emmental to retain that creamy, nutty essence.

Can I prepare the crust in advance?

Yes! You can make and chill the dough up to two days ahead, which makes preparing the tart much quicker on the day you plan to serve it.

Does the tart freeze well after baking?

It does freeze well, but the texture of the crust may be slightly less crisp after thawing. For best results, reheat in an oven rather than a microwave to restore some of the original crispness.

Final Thoughts

This Mushroom Tart with Gruyere and Thyme Recipe is one of those dishes that feels special yet effortless, with flavors that linger lovingly on the palate. Whether you’re baking it for a casual weeknight meal or a fancy brunch, it’s sure to impress and satisfy. So go ahead, gather your ingredients, and dive into the comforting, buttery goodness of this unforgettable tart. You truly can’t go wrong with it on your recipe roster!