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.
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.