Heat oven to 375°F. Spray large baking sheet with cooking spray.
Unroll can of dough. Place on baking sheet, firmly press perforations and seams to seal.
Place cheese slices, overlapping slightly, down centre of dough, leaving 1-inch border at each end. Top evenly with ham slices.
With kitchen scissors or sharp knife, make cuts 1 inch apart on long sides of dough rectangle to within 1/2 inch of filling. Alternately cross strips over filling. Bring short ends over filling, and press to seal. In small bowl, beat egg and water. Brush dough with egg mixture. Top with olives for mummy eyes.
Bake 20 to 25 minutes or until deep golden brown. Cut into crosswise slices.