1 (17 oz.) pkg. frozen puff pastry, thawed about 20 minutes, room temp.
Dijon style mustard
6 oz. sliced Swiss cheese, cut into 3 1/2" x 2" strips
6 oz. sliced baked or boiled ham, cut into 3 1/2" x 2" strips
1 egg, beaten

Roll each sheet of puff pastry out to a 12" square on a lightly floured board. Cut into 9 (4") squares. Repeat with remaining sheet of pastry. Spread each square lightly with mustard. Top half of each square with a strip of cheese. Fold squares of pastry in halves on line with the long edges of ham strips, moistening edges and pressing with a fork to seal. Place pastries about 2" apart on ungreased baking sheets. Brush lightly with egg. Pierce top of each pastry in several places with a fork. Bake at 400 degrees until puffed and golden brown, 15 to 18 minutes. Serve hot.