1

Spray a large nonstick skillet with olive-oil nonstick spray and set over medium-high heat. Add the mushrooms and cook, stirring, until all of the liquid evaporates, about 5 minutes. Stir in the thyme, salt, pepper, and half-and-half. Reduce the heat and simmer, uncovered, until the mushrooms are very soft and most of the half-and-half is absorbed, about 15 minutes. Transfer the contents of the pan to a food processor or blender and puree, scraping down the sides midway through if necessary. Cover and freeze for 45 minutes.

2

Preheat the oven to 400°F. On a lightly floured surface, roll out the puff pastry into an 81/2 x 11-inch rectangle. Leaving a 1/2-inch border all around, spread the chilled mushroom puree over the dough. Lay the fillets down the center. Fold the dough up around the fish and pinch closed. Gently transfer to a foil- or parchment-lined baking sheet, placing seam-side down. Spray with olive-oil nonstick spray and bake until well puffed and golden, about 30 minutes. Transfer to a platter and let stand 5 minutes before cutting into 6 slices.