This mushroom tart with puff pastry has a crisp, flaky crust topped with buttery mushrooms, soft golden onions, garlic, thyme, balsamic vinegar, and plenty of melted Gruyere cheese. It looks impressive enough for brunch or entertaining, but using ready-made puff pastry keeps the recipe surprisingly simple.
I especially love how savory the mushroom filling becomes once the onions, garlic, thyme, and balsamic cook together. If you love mushroom dinners, try my Creamy Mushroom Pasta next. For another savory bake, these Cheddar Cheese Scones are soft and cheesy, while my Easy Salad Recipes make a fresh side for the tart. A cold Cucumber Mint Lemonade is an easy drink to serve alongside.
The key is cooking the mushrooms before they go onto the pastry. Mushrooms release plenty of moisture, and removing most of that liquid in the skillet helps the puff pastry stay crisp instead of turning soggy.
What Is a Mushroom Tart?
A mushroom tart is a savory pastry topped or filled with cooked mushrooms and other ingredients such as onions, herbs, and cheese.
This version uses one sheet of puff pastry as the base. The mushrooms and onions are cooked separately until browned and tender, then combined with garlic, dried thyme, and balsamic vinegar.
The filling is spread over the pastry and topped with shredded Gruyere before baking.
The finished tart has a crisp golden edge, buttery mushroom filling, sweet-savory onions, and melted cheese in every slice.
Table of contents
Ingredients for Mushroom Tart with Puff Pastry
Let’s Make Mushroom Tart with Puff Pastry
- Prepare the Puff Pastry
Preheat the oven to 400°F (200°C).
Line a large baking sheet with parchment paper.
Unroll the puff pastry onto the prepared sheet.
Leave approximately a 1-inch border around the edge. Gently score the border with a knife without cutting completely through the pastry.
Return the pastry to the refrigerator while you prepare the mushroom filling.
- Cook the Onions
Melt the butter in a large skillet over medium heat.
Add the thinly sliced shallots or onion along with the dried thyme.
Season lightly with salt and black pepper.
Cook, stirring occasionally, until the onions soften and begin turning golden.
Add the minced garlic and cook briefly until fragrant.
Transfer the onion mixture to a plate or move it to one side while you cook the mushrooms.
- Brown the Mushrooms
Add the olive oil to the skillet.
Increase the heat slightly and add the sliced mushrooms.
Spread them out instead of piling them in the center of the pan.
Cook until they release their moisture and begin turning golden brown around the edges.
Avoid stirring constantly. Giving the mushrooms time against the hot pan helps them brown rather than steam.
- Finish the Mushroom Filling
Return the onion mixture to the skillet with the mushrooms.
Pour in the balsamic vinegar.
Season with additional salt and black pepper to taste.
Stir everything together and cook briefly until most of the excess moisture has evaporated.
Remove the skillet from the heat.
Allow the filling to cool for a few minutes before putting it onto the pastry.
- Assemble the Mushroom Tart
Remove the chilled puff pastry from the refrigerator.
Spread the mushroom and onion mixture evenly over the center, keeping the scored border uncovered.
Sprinkle the shredded Gruyere over the mushrooms.
Fold or gently shape the exposed pastry edge if needed to create a defined border.
Brush the pastry border with beaten egg.
- Bake
Transfer the tart to the preheated oven.
Bake for approximately 20–25 minutes, or until the puff pastry is well risen and golden around the edges and the Gruyere is melted and lightly browned.
If the pastry still looks pale after 20 minutes, continue baking and check it every few minutes.
- Cool and Slice
Let the tart cool on the baking sheet for about 5–10 minutes.
This gives the pastry a little time to firm up and makes it easier to cut clean slices.
Slice into wedges and serve warm.
How to Keep Puff Pastry Mushroom Tart from Getting Soggy
The biggest challenge with a mushroom puff pastry tart is moisture.
Mushrooms naturally release a lot of water as they cook. If they go onto the pastry raw, that moisture can soak into the base before the pastry has enough time to become crisp.
That is why I cook the mushrooms first.
Keep cooking until the liquid they release has mostly evaporated and the mushrooms begin browning.
The onion mixture should also be soft but not watery.
After adding the balsamic vinegar, give the mixture another moment in the skillet so any excess liquid cooks away.
Another important detail is cooling the filling slightly before spreading it onto the puff pastry. Very hot filling can soften the butter layers in the pastry before it reaches the oven.
Keep the pastry chilled while making the filling and assemble everything shortly before baking.
Finally, do not overload the tart. An overly thick layer of mushrooms and cheese traps more moisture against the pastry.
Common Mistakes to Avoid
- Putting raw mushrooms on the pastry: Mushrooms release too much water as they cook.
- Crowding the mushrooms in the skillet: They are more likely to steam than brown.
- Stirring the mushrooms constantly: Give them time against the pan to develop color.
- Leaving too much liquid in the filling: Cook until most of the moisture has evaporated.
- Adding garlic too early: Garlic can burn while the onions are still cooking.
- Using warm puff pastry: Keep it chilled until assembly.
- Adding piping-hot filling: Let the mushroom mixture cool briefly first.
- Covering the pastry border: Leave an uncovered edge so the pastry can rise properly.
- Skipping the egg wash: Egg gives the exposed crust a much more attractive golden finish.
- Cutting the tart immediately: A short rest helps the pastry hold its shape better.
What to Serve with Mushroom Tart
This mushroom and Gruyere tart works as an appetizer, brunch dish, light lunch, or meatless dinner.
For a lighter meal, serve a slice with a simple green salad, tomato salad, cucumber salad, or roasted vegetables.
Soup also works particularly well. Tomato soup, vegetable soup, or a smooth potato soup gives you a comforting meal without competing with the mushroom flavor.
For brunch, add eggs, fresh fruit, or another savory pastry.
You can also cut the tart into smaller pieces instead of wedges and serve it as a party appetizer.
FAQs
Yes. Puff pastry makes an excellent base for mushroom tart because it becomes crisp, flaky, and golden while the mushrooms cook into a savory topping.
The important part is cooking the mushrooms first so excess moisture does not soak into the pastry.
Yes, I strongly recommend it.
Pre-cooking the mushrooms removes much of their moisture and concentrates their flavor.
Gruyere is especially good because its nutty, savory flavor complements mushrooms and onions.
You can also use Swiss cheese, goat cheese, Parmesan, cheddar, or a combination.
Cook the mushrooms until their moisture has evaporated, cool the filling slightly, keep the puff pastry cold, and avoid overloading the pastry.
You can make the mushroom-onion filling ahead and refrigerate it.
For the crispiest pastry, assemble and bake the tart shortly before serving.
You might also like
More Recipes To Try
Swipe to see all 5 recipes
Mushroom Tart with Puff Pastry and Gruyere
Ingredients
Equipment
Method
- Preheat the oven to 400°F (200°C) and line a baking sheet with parchment paper.
- Unroll the puff pastry onto the prepared baking sheet. Score a border approximately 1 inch from the edge without cutting completely through the pastry. Refrigerate while preparing the filling.
- Melt the butter in a large skillet over medium heat.
- Add the sliced shallots or onion and dried thyme. Season lightly with salt and black pepper.
- Cook until the onions are softened and beginning to turn golden.
- Add the minced garlic and cook briefly until fragrant. Transfer the mixture out of the skillet.
- Add the olive oil and sliced mushrooms to the skillet.
- Cook until the mushrooms release their moisture and begin to brown.
- Return the onion mixture to the skillet. Add the balsamic vinegar and season with salt and black pepper.
- Cook briefly until most excess moisture has evaporated. Remove from the heat and allow to cool slightly.
- Spread the mushroom and onion filling over the center of the puff pastry, keeping the border clear.
- Sprinkle the Gruyere evenly over the filling.
- Brush the exposed pastry border with beaten egg.
- Bake for 20–25 minutes, or until the pastry is puffed and deep golden and the cheese is melted.
- Let rest for 5–10 minutes before slicing and serving.
Nutrition
Video
Tried this recipe?
Let us know how it was!Estimated reading time: 8 minutes
