These caramelized mushroom puff pastry tarts are an easy, savory treat that come together in about 30 minutes! Layered with puff pastry, gruyere cheese, and caramelized mushrooms and onions, they're the perfect appetizer!
You just need a few simple ingredients to make these mushroom puff pastry tarts!
- Puff Pastry - I always use frozen puff pastry for these tarts! Just place the box in the fridge the night before you plan to make the tarts, and the pastry will be perfectly thawed and ready to use!
- Mushrooms - You can use whatever mushrooms you prefer! I love using either cremini, porcini, or a mix of wild mushrooms!
- Onions - You can use either sweet onions or shallots for these tarts!
- Gruyere Cheese - Gruyere is one of my favorite types of cheese! It has a creamy, nutty flavor that just pairs beautifully with the umami of the mushrooms! But these mushroom tarts would also be delicious with brie or fontina cheese!
- Fresh Thyme - I love the combo of fresh thyme and mushrooms but fresh sage would also be delicious!
tips for baking with frozen puff pastry
- Start with puff pastry that has been fully defrosted! The best way to defrost puff pastry is by placing it in the fridge overnight!
- Puff pastry is easiest to work with when it's still cold, but pliable which is why refrigerating it overnight is the best!
- Use a sharp knife or pizza cutter to cut the puff pastry into rectangles. You don't want to smash the edges as that will cause the pastry not to puff up as much.
- Always baking using parchment paper or a silicone mat, so that the puff pastry doesn't stick to the pan.
How to Make Mushroom Tarts
Melt the butter in a small pan over medium heat.
Thinly slice the onion, mushrooms, and garlic. Add to the pan and sauté gently for 10-20 minutes, stirring occasionally, until aromatic and caramelized. Season with salt and pepper to taste.
Preheat the oven to 425°F and line a baking sheet with parchment paper (this recipe makes 12 tarts so you'll probably need 2 baking sheets).
Cut each puff pastry sheet into 6 equal rectangles and arrange on your baking sheet.
If desired, lightly brush the edges of the pastry with egg wash.
Spread the shredded gruyere over the top of the pastry.
Then add the caramelized mushrooms and onions over top of the cheese and sprinkle with fresh thyme.
Bake at 425°F for 15-20 minutes or until the pastry is golden brown and the cheese is melted and bubbly.
Serve the mushroom puff pasty tarts warm and enjoy!!
These tarts are best served the same day, but will keep in an airtight container in the fridge for up to 3 days.
Tips for Success!
For best results I always recommend using weight measurements (especially when baking) because it's the most accurate. Kitchen scales are super affordable and also reduce the number of dishes you have to do! However, all my recipes also include US customary measurements for convince. Use this chart to convert measurements for common ingredients!
Substitutions: In all my recipes, I've included substitutions that I know will work, but I cannot guarantee results if you substitute ingredients that I have not recommended. For example, granulated sugar and honey are indeed both sweeteners but they have different properties so that can not always be swapped 1:1. In the recipe card you'll find links to the specific ingredients/brands that I use.
A note on salt: I almost exclusively use Diamond Crystal Kosher Salt because it's the best all-purpose salt for cooking and baking. If you're not using kosher salt, consult this handy guide for a conversion chart! When in doubt, if you're using table salt just reduce the amount by half for baked goods. When cooking, I prefer to under-salt because you can always add more! If you've over-salted, adding a little bit of acid (like lemon juice) can help.
More Recipes You Might Like!
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Caramelized Mushroom Puff Pastry Tarts with Gruyere
- ¼ cup unsalted butter
- 16 ounces cremini mushrooms, sliced
- 2 large yellow onion, sliced (substitute shallots)
- 4 cloves garlic, sliced
- ½ teaspoon kosher salt
- ½ teaspoon black pepper
- 2 sheets frozen puff pastry, thawed (1 box)
- 1 large egg, beaten for egg wash
- 1 cup Gruyere cheese, shredded
- 2 teaspoons fresh thyme
- Melt the butter in a small pan over medium heat.
- Thinly slice the onion, mushrooms, and garlic. Add to the pan and sauté gently for 10-20 minutes, stirring occasionally, until aromatic and caramelized. Season with salt and pepper to taste.
- Preheat the oven to 425°F and line a baking sheet with parchment paper (this recipe makes 12 tarts so you'll probably need 2 baking sheets).
- Cut each puff pastry sheet into 6 equal rectangles and arrange on your baking sheet.
- If desired, lightly brush the edges of the pastry with egg wash.
- Spread the shredded gruyere over the top of the pastry.
- Then add the caramelized mushrooms and onions over top of the cheese and sprinkle with fresh thyme.
- Bake at 425°F for 15-20 minutes or until the pastry is golden brown and the cheese is melted and bubbly.
- Serve the mushroom puff pasty tarts warm and enjoy!!
The nutritional information on this website is only an estimate and is provided for convenience and as a courtesy only. The accuracy of the nutritional information for any recipe on this site is not guaranteed.