- One 1 ½ pound butternut squash
- ¼ cup extra-virgin olive oil
- Kosher salt and freshly ground pepper
- 2 tablespoons unsalted butter
- 1 large shallot
- 1 pound assorted mushrooms, trimmed and cut
- 1 teaspoon sherry vinegar
- Large pinch of dried nutmeg
- All-purpose flour, for dusting
- 14 ounces chilled all-butter puff pastry
- 2 large egg yolks
- ¼ cup creme fraiche
- ¼ pound Gruyere cheese
- 2 teaspoons chopped thyme
STEP 1: The Squash
- Preheat the oven to 375°
- Peel, seed and cut the Squash into ½ inch pieces.
- Toss cut squash in a bowl with 2 tablespoons of the oil.
- Spread the squash on a baking sheet, season with salt & pepper.
- Bake for 25 minutes, until just tender, transfer to a bowl.
- Increase the temperature to 400°.
STEP 2: Mushrooms & Shallots
- Meanwhile, in a skillet, melt the butter in the remaining 2 tablespoons oil.
- Thinly slice the shallot, add the shallot and cook over moderate heat, stirring, until softened.
- Trim and cut mushrooms into 1 inch pieces, add to shallots, cover and cook, stirring until tender, approximately 7 minutes.
- Season with salt and pepper and remove from the heat. Toss with the vinegar and nutmeg and add to squash.
STEP 3: The Pastry
- Line a baking sheet with parchment paper.
- On a floured work surface, roll the puff pastry out to 12 ½ by 14 ½ inches. Using a knife trim the pastry to 12 by 14 inches.
- Transfer to the baking sheet and prick the pastry with a fork all over except for a ½ inch border.
- Bake the pastry for 20 minutes, until golden; pierce with a fork if it puffs during baking. Let cool.
STEP 4: Cheese & Herbs
- Grate the Gruyere.
- Chop the thyme.
- Stir the egg yolks, creme fra’iche, Gruyere, thyme, 1/2 teaspoon of salt and 1/4 teaspoon of pepper into the mushrooms and squash. Spread the mixture on the pastry inside the border.
- Bake for 15 minutes, until the cheese is melted.