Ingredients :
- 1 tablespoon butter
- 8 ounces baby Portobello mushrooms or other mushrooms, sliced
- 1 leek white part only, halved lengthwise and thinly sliced
- Salt and freshly ground black pepper
- 1 clove garlic minced
- 8 ounces havarti cheese shredded
- 1 teaspoon minced fresh thyme or ½ teaspoon dried thyme
- 1/4 teaspoon dried basil
- 1/4 cup heavy cream
- 1 package frozen puff pastry thawed
- 1 egg plus 1 tablespoon water, lightly beaten
- 1/2 cup shredded Parmesan cheese
Directions :
- Arrange two oven racks to the upper and lower middle positions and preheat the oven to 400 degrees. Line 2 rimmed baking sheets with parchment paper or silicone mats.
- In a large skillet, melt butter until foaming. Add mushrooms, leeks, and a pinch of salt and sauté until tender, about 10 minutes (the first 7 minutes will be the mushrooms releasing their liquid, and then it will evaporate). Stir in the garlic until fragrant, about 30 seconds.
- Add havarti cheese, thyme, basil, and the heavy cream. Bring the mixture to a boil and stir until the mixture has thickened, about 2 minutes. Season to taste with salt and pepper (I used just a pinch of salt because the cheese was rather salty). Remove from heat and cool slightly (you'll have about 2 cups filling).
- Unfold both sheets of puff pastry and place one on each prepared baking sheet. Spoon half the cheese mixture onto the middle of each crust (about 1 cup per crust). Fold the edges over to form the rim of the tart.
- In a small bowl, whisk the egg and water together to create an egg wash. Using a pastry brush, brush the edges of the each of the tarts. Divide the Parmesan between the tarts, sprinkling it over the top.
- Bake until the pastry is deep golden brown in color, approximately 20 to 25 minutes. Cool 5 minutes. Serve warm or at room temperature.
