Heat oven to 400 degrees F. In a bowl
, stir together cheese
, half-and-half, sage and pepper. On a lightly floured surface, roll out 1 pastry sheet to a 12-inch square; cut into 9 squares. Working with one square at a time, brush edges with egg and place 1 tbsp. filling in center. Fold together opposite corners of square, forming a triangle, and press together edges to seal; decorate with tines of a fork. Transfer to a baking sheet
, brush with egg and prick top of each once with a fork. Repeat with remaining pastry sheet, filling and egg.