Mushroom and Caramelized Onion Phyllo Tart

Mushroom and Caramelized Onion Phyllo Tart is a flaky, flavor-packed vegetarian delight you can make at home with simple steps.

Mushroom and Caramelized Onion Phyllo Tart — introduction

This Mushroom and Caramelized Onion Phyllo Tart brings big taste with light, crisp phyllo layers. It works for a weeknight dinner or a simple party dish and feels special without fuss.

If you like savory tarts, try a related baked dish like the creamy potato mushroom and brie bake with caramelized onions for another idea.

Why make Mushroom and Caramelized Onion Phyllo Tart

Make this Mushroom and Caramelized Onion Phyllo Tart because it is:

• Vegetarian and full of flavor.
• Crisp outside and soft inside.
• Great hot or at room temperature for guests.

This tart also pairs nicely with robust sides or sandwiches like the caramelized onion and garlic burger with creamy herb sauce for a fuller meal.

How to make Mushroom and Caramelized Onion Phyllo Tart

Follow simple steps to build and bake the tart. Work on the onions and mushrooms first, then layer phyllo and cheese, fill, fold, and bake.

Ingredients for Mushroom and Caramelized Onion Phyllo Tart

• 1 package phyllo dough, thawed
• 8 ounces mixed mushrooms, thinly sliced
• 1 large sweet onion, thinly sliced
• 2–3 garlic cloves, minced
• 1/2 cup vegetable broth
• 1 tablespoon honey
• 1 tablespoon fresh thyme leaves (or 1 teaspoon dried)
• 1–2 sprigs fresh rosemary, finely chopped
• Red pepper flakes, to taste
• Salt, to taste
• Black pepper, to taste
• 1/3 cup shredded Gruyère-style cheese
• 1/3 cup shredded Fontina-style cheese
• 8 ounces fresh mozzarella, sliced or torn
• 1/4 cup fresh basil leaves, torn (for finishing)
• 1/2 cup unsalted butter, melted
• 2–3 tablespoons olive oil

Directions for Mushroom and Caramelized Onion Phyllo Tart

1. Heat the oven to 375°F. Line a large baking sheet with parchment paper and set aside.
2. Warm 2 tablespoons olive oil in a large oven-safe skillet over medium heat. Add the onions and cook 3–4 minutes until they soften.
3. Stir in honey, a pinch of salt, and black pepper. Pour in half the vegetable broth and cook 5–6 minutes, letting most liquid evaporate. Add the rest of the broth and cook 6–8 minutes until onions are deep golden.
4. Add mushrooms, garlic, thyme, rosemary, and a pinch of red pepper flakes. Mix, then place the skillet in the oven and roast about 10 minutes to deepen flavors.
5. Lay one sheet of phyllo on the baking sheet and brush lightly with melted butter. Add another sheet and brush again. Layer 3–4 sheets.
6. Place additional sheets at slight angles so corners don’t line up, brushing butter between each, until 9–10 sheets are used.
7. Drizzle a little olive oil over the phyllo center. Sprinkle the shredded Gruyère and Fontina evenly over the middle, leaving a 2-inch border. Spoon the mushroom and onion mix over the cheese, then scatter mozzarella on top.
8. Gently fold the outer phyllo edges up and over the filling, pleating as needed. Lightly brush the folded edges with olive oil.
9. Bake 30–35 minutes until phyllo is golden and crisp and cheese is melted and lightly browned.
10. Let the tart cool a bit before slicing. Sprinkle with torn fresh basil just before serving.

How to serve Mushroom and Caramelized Onion Phyllo Tart

Serve the Mushroom and Caramelized Onion Phyllo Tart warm or at room temperature. Cut into slices or squares for easy sharing.

For a hearty plate, add a warm side like the cheesy caramelized onion and bacon potato gratin or a simple green salad.

How to store Mushroom and Caramelized Onion Phyllo Tart

• Cool the tart completely before storing.
• Cover well and keep in the fridge up to 3 days.
• Reheat in a 350°F oven for 10–12 minutes to crisp the phyllo again.

Tips to make Mushroom and Caramelized Onion Phyllo Tart

• Work quickly with phyllo to keep it from drying. Cover sheets with a damp towel.
• Let onions brown slowly for best flavor.
• Use a mix of mushrooms for depth.
• Brush each phyllo layer lightly for even crispness.

Variation for Mushroom and Caramelized Onion Phyllo Tart

• Add a spoon of goat cheese for tang.
• Swap mozzarella for feta or ricotta for a different texture.
• Add roasted peppers or spinach for color and extra veg.

FAQs about Mushroom and Caramelized Onion Phyllo Tart

Q: Can I use frozen phyllo for Mushroom and Caramelized Onion Phyllo Tart?
A: Yes. Thaw it in the fridge overnight and keep it covered while you work.

Q: Can I make the filling ahead for Mushroom and Caramelized Onion Phyllo Tart?
A: Yes. Make the mushroom and onion mix up to 2 days ahead and store in the fridge. Reheat slightly before filling.

Q: Where can I buy phyllo dough for the tart?
A: Buy it here.

Q: Is this tart freezer friendly?
A: You can freeze baked slices wrapped well for up to 1 month. Reheat from frozen in the oven at 350°F until hot.

Q: Can I make a smaller tart with this recipe?
A: Yes. Use fewer phyllo sheets and less filling, and reduce bake time slightly.

Mushroom and Caramelized Onion Phyllo Tart

A flaky, flavor-packed vegetarian delight made with layers of phyllo, mushrooms, and caramelized onions, perfect for dinner or parties.

Print Recipe Pin Recipe

Prep Time 20 minutes mins

Cook Time 45 minutes mins

Total Time 1 hour hr 5 minutes mins

Course Appetizer, Main Course

Cuisine Mediterranean, Vegetarian

Servings 8 servings

Calories 300 kcal

Ingredients

  

For the Tart

• 1 package phyllo dough, thawed
• 8 ounces mixed mushrooms, thinly sliced
• 1 large sweet onion, thinly sliced
• 2–3 cloves garlic, minced
• 1/2 cup vegetable broth
• 1 tablespoon honey
• 1 tablespoon fresh thyme leaves or 1 teaspoon dried
• 1–2 sprigs fresh rosemary, finely chopped
• to taste Red pepper flakes
• to taste Salt
• to taste Black pepper
• 1/3 cup shredded Gruyère-style cheese
• 1/3 cup shredded Fontina-style cheese
• 8 ounces fresh mozzarella, sliced or torn
• 1/4 cup fresh basil leaves, torn for finishing
• 1/2 cup unsalted butter, melted
• 2–3 tablespoons olive oil

Instructions

 

Preparation

• Heat the oven to 375°F. Line a large baking sheet with parchment paper and set aside.
• Warm 2 tablespoons olive oil in a large oven-safe skillet over medium heat. Add the onions and cook for 3–4 minutes until they soften.
• Stir in honey, a pinch of salt, and black pepper. Pour in half the vegetable broth and cook for 5–6 minutes, letting most liquid evaporate.
• Add the rest of the broth and cook for another 6–8 minutes until onions are deep golden.
• Add mushrooms, garlic, thyme, rosemary, and a pinch of red pepper flakes. Mix, then place the skillet in the oven and roast for about 10 minutes to deepen flavors.

Assembling the Tart

• Lay one sheet of phyllo on the baking sheet and brush lightly with melted butter. Add another sheet and brush again. Layer 3–4 sheets.
• Place additional sheets at slight angles so corners don’t line up, brushing butter between each, until 9–10 sheets are used.
• Drizzle a little olive oil over the phyllo center. Sprinkle the shredded Gruyère and Fontina evenly over the middle, leaving a 2-inch border.
• Spoon the mushroom and onion mix over the cheese, then scatter mozzarella on top.
• Gently fold the outer phyllo edges up and over the filling, pleating as needed. Lightly brush the folded edges with olive oil.

Baking

• Bake for 30–35 minutes until phyllo is golden and crisp and cheese is melted and lightly browned.
• Let the tart cool a bit before slicing. Sprinkle with torn fresh basil just before serving.

Notes

Work quickly with phyllo to keep it from drying. Cover sheets with a damp towel. Let onions brown slowly for best flavor. Use a mix of mushrooms for depth. Brush each phyllo layer lightly for even crispness.

Keyword Caramelized Onion, Mushroom Tart, Phyllo Tart, Savory Tart, Vegetarian Dish