This savory butternut squash & mushroom tart recipe comes together with puff pastry dough, vegetables, herbs, and parmesan cheese. You can use store-bought puff pastry or homemade pastry dough.
- 1 lb homemade rough puff pastry or store-bought frozen & thawed puff pastry (2 sheets)
- egg wash: 1 large egg beaten with 1 Tablespoon (15ml) water or milk
- 1 Tablespoon (15ml) olive oil
- 2 cups (about 270g) peeled & sliced butternut squash (1/4 inch slices)
- 1 and 1/4 cups (150g) sliced or roughly chopped mushrooms
- 1/2 cup sliced onion (1/2 of a medium onion)
- 3 garlic cloves, minced
- 1/4 teaspoon salt
- pinch ground pepper, plus more for garnish
- 2 teaspoons fresh thyme leaves (or 1 teaspoon dried)
- 2 teaspoons chopped fresh rosemary (or 1 teaspoon dried)
- pinch ground nutmeg
- 1 cup (120g) shredded parmesan cheese
- optional for garnish: flaky sea salt, pepper, more cheese, more fresh thyme & rosemary
- Dough: Prepare homemade rough puff pastry dough through 2nd refrigeration. If using store-bought frozen puff pastry, make sure it’s thawed. Keep either dough in the refrigerator until step 4 below.
- Topping: Over low-medium heat in a large skillet, cook oil and butternut squash together for 5 minutes stirring occasionally. Add mushrooms, onion, garlic, salt, pepper, thyme, rosemary, and nutmeg. Cook until vegetables are soft, about 5-6 minutes. Remove from heat.
- Preheat oven to 400°F (204°C). Line a large baking sheet with parchment paper or a silicone baking mat. Set aside.
- On a lightly floured work surface using a lightly floured rolling pin, roll pastry dough into a 10×16 inch rectangle. (Tip if using store-bought– place the edge of one sheet over the other and use a rolling pin to adhere them together. Roll the whole thing out into a 10×16 inch rectangle.) Carefully transfer dough to lined baking sheet. If dough has lost shape, use your hands to reshape into a rectangle. Fold over a 1/2 inch edge and crimp edges down with a fork. Crimping is much easier the colder the pastry is, so place dough/baking sheet into the refrigerator to chill for 10 minutes if needed.
- Egg Wash & Assemble: Brush egg wash all over puff pastry including the edges. Use a fork to poke holes all over the dough (not the crimped edge). Sprinkle with 3/4 cup (about 95g) cheese. Spoon vegetable topping over cheese and arrange in a single layer as best you can.
- Bake tart for 30 minutes. Remove from the oven and sprinkle remaining cheese all over the top. Return to the oven and bake for 5-8 more minutes or until cheese is melted and pastry is golden brown.
- Remove from the oven and, if desired, garnish with flaky sea salt, a sprinkle of pepper, and/or extra cheese and herbs. Slice and serve warm or at room temperature.
- Make Ahead & Freezing Instructions: If using homemade dough, see the detailed rough puff pastry recipe instructions for make-ahead and freezing details. You can essentially prep the dough 48 hours in advance or freeze up to 1 month. You can also make the vegetable topping ahead of time. Complete step 2 and then cover and refrigerate for up to 1 day before layering on the tart. (No need to bring to room temperature before using.) You can also assemble the entire tart through step 5 ahead of time. Cover and place in the refrigerator for up to 1 day before baking. No need to bring to room temperature before baking. You can freeze the baked and cooled tart for up to 3 months. It’s best to freeze the slices between sheets of parchment paper. Thaw in the refrigerator and reheat (covered) in a 300°F (149°C) oven for 15 minutes before serving.
- Toppings: Use any mushroom variety that you enjoy. I usually use a mix of white button mushrooms and shiitake. Feel free to skip the mushrooms and use more butternut squash in its place. You can also switch up the herbs if desired or replace the cheese with goat, white cheddar, and Gruyère cheeses.
- Frozen Butternut Squash: If using frozen butternut squash, thaw first and then cook with the oil and remaining topping ingredients (except the cheese) for 5-6 minutes or until mushrooms and squash are soft.
Keywords: butternut squash mushroom tart