Delicious Onion Mushroom Tart Recipe for Every Occasion

Onion Mushroom Tart is a savory dish featuring a flaky crust filled with caramelized onions, mushrooms, and cheese. This delightful tart brings together rich flavors and textures, making it a perfect centerpiece for any meal. Whether you’re hosting a dinner party or simply enjoying a quiet night at home, this tart is sure to impress. With its deliciously creamy filling and a golden, flaky crust, you’ll find that every bite is a delightful experience.

Why You’ll Love This Onion Mushroom Tart

This Onion Mushroom Tart is not just a feast for the eyes; it’s packed with flavor and nutrition. Here’s why you’ll love it:

• Perfect for any occasion, from casual dinners to gourmet gatherings.
• Vegetarian-friendly, making it a great option for meatless meals.
• Easy to prepare, even for novice cooks.
• Can be made ahead of time and served warm or at room temperature.
• Versatile: it pairs well with salads or can be enjoyed on its own.
• With caramelized onions and mushrooms, it offers a delicious umami flavor.
• Healthy options can be incorporated easily for a lighter version.

Ingredients for Onion Mushroom Tart

Gather these items:

• 1 1/4 cups all-purpose flour
• 1/2 teaspoon salt
• 1/2 cup unsalted butter (cold and cubed)
• 3–4 tablespoons ice water
• 2 tablespoons olive oil
• 2 large onions (thinly sliced)
• 8 ounces mushrooms (sliced, such as cremini or button)
• 2 cloves garlic (minced)
• 1 teaspoon fresh thyme (or 1/2 teaspoon dried thyme)
• Salt and pepper (to taste)
• 1/2 cup heavy cream
• 2 large eggs
• 1/2 cup grated cheese (such as Gruyère or Parmesan)

How to Make Onion Mushroom Tart Step-by-Step

1. Step 1: In a mixing bowl, combine the flour and salt.
2. Step 2: Add the cold, cubed butter to the flour mixture. Work the butter into the flour until the mixture resembles coarse crumbs.
3. Step 3: Gradually add ice water, one tablespoon at a time, mixing until the dough comes together. Do not overmix.
4. Step 4: Shape the dough into a disk, wrap it in plastic wrap, and refrigerate for at least 30 minutes.
5. Step 5: In a large skillet, heat the olive oil over medium heat. Add the sliced onions and a pinch of salt. Cook for about 20–25 minutes until the onions are golden brown and caramelized.
6. Step 6: Stir in the sliced mushrooms and minced garlic. Cook for an additional 5–7 minutes until the mushrooms are tender. Add thyme, salt, and pepper to taste. Remove from heat and let cool slightly.
7. Step 7: Preheat your oven to 375°F (190°C).
8. Step 8: On a floured surface, roll out the chilled dough into a circle about 12 inches in diameter. Transfer to a 9-inch tart pan, pressing it into the edges. Trim any excess dough.
9. Step 9: Prick the bottom of the crust with a fork. Place parchment paper over the crust and fill with pie weights or dried beans. Bake for 15 minutes. Remove the weights and parchment, and bake for an additional 5 minutes until lightly golden.
10. Step 10: In a bowl, whisk together the heavy cream and eggs. Season with salt and pepper.
11. Step 11: Spread the caramelized onion and mushroom mixture evenly over the tart crust. Pour the egg and cream mixture over the top, then sprinkle with grated cheese.
12. Step 12: Bake the tart for 25–30 minutes, or until the filling is set and the top is golden brown.
13. Step 13: Allow the tart to cool for a few minutes before slicing. Serve warm or at room temperature.

Pro Tips for the Perfect Onion Mushroom Tart

Keep these in mind:

• Use fresh ingredients for best flavor.
• Let the tart cool slightly for easier slicing.
• Experiment with different cheeses for varied taste.
• Consider adding spinach for a healthy twist on your Onion Mushroom Pastry.
• A sprinkle of nutmeg can add depth to your filling.

Best Ways to Serve Onion Mushroom Tart

This delicious Caramelized Onion and Mushroom Tart can be served in various delightful ways:

• Pair it with a fresh green salad for a light lunch.
• Serve as an appetizer at your next gathering.
• Enjoy it alongside a hearty soup for a complete meal.

How to Store and Reheat Onion Mushroom Tart

To store, keep any leftovers in an airtight container in the fridge. The tart can be reheated in an oven at 350°F (175°C) for about 15 minutes. This method helps maintain the crust’s flakiness, making it perfect for meal prep!

Frequently Asked Questions About Onion Mushroom Tart

What’s the secret to perfect Onion Mushroom Tart?

The secret lies in the caramelization of the onions. Take your time to cook them until they are deeply golden and sweet. This enhances the overall flavor, making your Savory Onion Mushroom Pie truly delicious.

Can I make Onion Mushroom Tart ahead of time?

Yes! You can prepare the tart a day in advance. Just bake it, let it cool, and store it in the fridge. Reheat before serving for the best taste.

How do I avoid common mistakes with Onion Mushroom Tart?

Ensure your dough is well-chilled before rolling it out, and avoid overcooking the filling. This way, your Flaky Onion Mushroom Tart will have the perfect texture and flavor.

Variations of Onion Mushroom Tart You Can Try

Feel free to experiment with these variations:

• Add spinach or kale for a Vegetarian Onion Mushroom Tart.
• Substitute goat cheese for a tangy flavor twist.
• Incorporate sun-dried tomatoes for an Italian flair.
• Use puff pastry instead of traditional crust for a lighter, flaky option.

For more delicious vegetarian recipes, check out this Irresistible Thai Red Curry Kabobs or try this Creamy Sausage Potato Chowder for a hearty meal. If you’re interested in the health benefits of mushrooms, you can read more here.

Delicious Onion Mushroom Tart Recipe for Every Occasion

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• Author: Anna
• Total Time: 1 hour
• Yield: 8 servings 1x
• Diet: Vegetarian

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Description

Onion Mushroom Tart is a savory dish featuring a flaky crust filled with caramelized onions, mushrooms, and cheese.

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Ingredients

Scale 1x2x3x

• For the Tart Crust:
• 1 1/4 cups all-purpose flour
• 1/2 teaspoon salt
• 1/2 cup unsalted butter (cold and cubed)
• 3–4 tablespoons ice water
• For the Filling:
• 2 tablespoons olive oil
• 2 large onions (thinly sliced)
• 8 ounces mushrooms (sliced, such as cremini or button)
• 2 cloves garlic (minced)
• 1 teaspoon fresh thyme (or 1/2 teaspoon dried thyme)
• Salt and pepper (to taste)
• 1/2 cup heavy cream
• 2 large eggs
• 1/2 cup grated cheese (such as Gruyère or Parmesan)

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Instructions

1. In a mixing bowl, combine the flour and salt.
2. Add the cold, cubed butter to the flour mixture. Work the butter into the flour until the mixture resembles coarse crumbs.
3. Gradually add ice water, one tablespoon at a time, mixing until the dough comes together. Do not overmix.
4. Shape the dough into a disk, wrap it in plastic wrap, and refrigerate for at least 30 minutes.
5. In a large skillet, heat the olive oil over medium heat. Add the sliced onions and a pinch of salt. Cook for about 20–25 minutes until the onions are golden brown and caramelized.
6. Stir in the sliced mushrooms and minced garlic. Cook for an additional 5–7 minutes until the mushrooms are tender. Add thyme, salt, and pepper to taste. Remove from heat and let cool slightly.
7. Preheat your oven to 375°F (190°C).
8. On a floured surface, roll out the chilled dough into a circle about 12 inches in diameter. Transfer to a 9-inch tart pan, pressing it into the edges. Trim any excess dough.
9. Prick the bottom of the crust with a fork. Place parchment paper over the crust and fill with pie weights or dried beans. Bake for 15 minutes. Remove the weights and parchment, and bake for an additional 5 minutes until lightly golden.
10. In a bowl, whisk together the heavy cream and eggs. Season with salt and pepper.
11. Spread the caramelized onion and mushroom mixture evenly over the tart crust. Pour the egg and cream mixture over the top, then sprinkle with grated cheese.
12. Bake the tart for 25–30 minutes, or until the filling is set and the top is golden brown.
13. Allow the tart to cool for a few minutes before slicing. Serve warm or at room temperature.

Notes

• Use fresh ingredients for best flavor.
• Let the tart cool slightly for easier slicing.
• Experiment with different cheeses for varied taste.

• Prep Time: 30 minutes
• Cook Time: 30 minutes
• Category: Savory Pie
• Method: Baking
• Cuisine: French

Nutrition

• Serving Size: 1 slice
• Calories: 250
• Sugar: 2g
• Sodium: 300mg
• Fat: 18g
• Saturated Fat: 10g
• Unsaturated Fat: 6g
• Trans Fat: 0g
• Carbohydrates: 20g
• Fiber: 2g
• Protein: 6g
• Cholesterol: 60mg

Written by Chef Anna

I'm Anna - a Le Cordon Bleu-trained chef, recipe developer, and the voice behind Chef Johns Gourmet. After a decade in professional kitchens, I now spend my mornings testing recipes and my afternoons writing them down so you can make them perfectly in your own kitchen. Every one of the 1,100+ recipes on this site has been personally cooked, tasted, and refined. I write like I'm standing next to you, walking you through every step. Simple recipes. Bold flavors. Made for real kitchens.