1 sheet frozen puff pastry
3/4 cup (3 ounces) Wisconsin Emmentaler Swiss cheese, shredded and divided
2 medium Bosc pears, peeled, cored, and sliced
1 tablespoon sugar
1/2 teaspoon ground cardamom
1/3 cup chopped walnuts
1 egg, lightly beaten
Thaw pastry for 20 minutes.
Preheat the oven to 350°F. Unfold pastry and cut into two rectangles. Roll each on a lightly-floured surface. Make one 6x13-inch, and the other 7x14-inch. Fold smaller piece in half, lengthwise, and cut through the folded edge to make slits about 2 inches long and 1/2 inch apart. Set aside.
Place larger rectangle on parchment-lined cookie sheet; sprinkle half the Swiss Cheese down center, leaving a 1/2-inch border; arrange pears on top. Sprinkle with remaining cheese, sugar, cardamom, and walnuts. Brush edges of the dough with egg. Place reserved pastry over top. Press edges together with tines of fork; brush with egg mixture (discard any remaining egg). Trim excess pastry to make sides even. Bake for 30 minutes, or until puffed and golden.