Vegan Mushroom Pie With Melted Leeks & Herbs
This recipe crafts a savory vegan mushroom pie featuring deeply caramelized leeks and a medley of earthy mushrooms. A rich, herbed filling, thickened with miso and flour, is encased in flaky puff pastry and baked until golden. It’s a comforting and flavorful plant-based main course, perfect for an elegant yet hearty meal.
Equipment
- 1 Large Skillet or Dutch Oven For sautéing vegetables and preparing the filling
- 1 Cutting Board
- 1 Chef's knife
- 1 Pie Dish or Baking Dish (9-inch)
- 1 Pastry Brush For brushing the puff pastry
Ingredients
Main
- 4 tablespoons extra-virgin olive oil divided
- 2 large or 3 medium leeks tough outer layers removed, halved lengthwise, washed very well and white and pale green parts sliced thinly
- 1 pound mixed mushrooms sliced (a mixture of shiitake, cremini, oyster, maitake, and trumpet would be excellent)
- Kosher salt and freshly ground black pepper to taste
- 1 pinch red pepper flakes
- 2 tablespoons vegan butter substitute more olive oil if you don’t like or have this
- 2 cloves garlic finely chopped
- 5 to 6 sprigs thyme leaves only
- 5 5 to 6 sage leaves thinly sliced into ribbons
- 1 tablespoon white miso
- 2 tablespoons all-purpose flour
- 1/4 cup dry white wine cider vinegar, or apple cider (hard or not)
- 1 3/4 cups vegetable stock or plain unsweetened oat milk for a richer texture, at room temperature
- 2 tablespoons nutritional yeast optional
- 1 sheet vegan puff pastry like Pepperidge Farm, thawed
- Aquafaba or melted vegan butter for brushing
Instructions
- Prepare leeks by removing tough outer layers, halving, washing thoroughly, and thinly slicing the white and pale green parts. Slice all mushrooms.
- Heat 2 tablespoons of olive oil in a large skillet over medium-low heat. Add sliced leeks with a pinch of salt and cook until very soft and melted, about 10-15 minutes. Remove leeks and set aside.
- Increase heat to medium-high. Add the remaining 2 tablespoons of olive oil. Sear mushrooms in batches if necessary, until deeply browned and caramelized, seasoning with salt and pepper. Return leeks to the pan.
- Reduce heat to medium, add vegan butter, chopped garlic, thyme leaves, sage ribbons, and red pepper flakes. Sauté for 1-2 minutes until fragrant.
- Stir in the white miso until it dissolves. Sprinkle all-purpose flour over the mixture and cook, stirring constantly, for 1 minute to cook out the raw flour taste.
- Deglaze the pan with dry white wine, cider vinegar, or apple cider, scraping up any browned bits. Gradually whisk in vegetable stock or oat milk, and nutritional yeast (if using). Bring to a simmer and cook, stirring, until the mixture thickens, about 5-7 minutes.
- Remove the filling from heat, taste, and adjust seasoning as needed. Transfer the filling to a bowl and let it cool completely, preferably in the refrigerator, to ensure it's firm.
- Preheat your oven to 400°F (200°C). Transfer the cooled mushroom and leek filling into a 9-inch pie dish or similar baking dish.
- Carefully lay the thawed vegan puff pastry sheet over the filling. Trim and crimp the edges to seal. Cut a few vents into the top of the pastry for steam to escape. Brush the top with aquafaba or melted vegan butter for a golden finish.
- Bake for 30-35 minutes, or until the puff pastry is beautifully golden brown and well-puffed. Let the pie rest for 5-10 minutes before slicing and serving.
Notes
Achieving proper browning on the mushrooms in batches is crucial for developing deep umami, the foundation of this pie. Ensure leeks are meticulously washed to remove all grit; their sweetness is vital once melted. When incorporating the flour, whisk continuously to prevent lumps and create a smooth béchamel-like base. Using room-temperature stock or oat milk helps achieve this. White miso adds significant depth; adjust salt accordingly. Keep your puff pastry chilled until just before assembly to ensure optimal flakiness. Allow the filling to cool completely before topping with pastry to prevent a soggy crust. For an extra layer of complexity, a hint of smoked paprika can be added with the herbs.