Prepare Strudel Dough as directed. For filling, drain tomatoes, reserving oil. Chop tomatoes. In a medium bowl combine tomatoes, cream cheese, olives, onions, egg yolk, basil, and 1/2 teaspoon pepper. If necessary, stir in enough reserved tomato oil (about 1 tablespoon) to make of spreading consistency. Lightly grease a large baking sheet; set aside.
To assemble strudel, prepare dough as directed in recipe. Beginning 4 inches from one of the 20-inch sides of dough, spread filling across the dough in a 4-inch-wide band.
Using the cloth beneath dough as a guide, gently lift 4-inch section of dough and lay it over filling. Slowly and evenly lift cloth and tightly roll up dough and filling, jelly-roll style. If needed, cut excess dough from ends to within 1 inch of the filling. Fold ends under to seal.
Transfer to prepared baking sheet. Curve the ends to form a crescent shape. Combine egg white and 1 tablespoon water; brush over top. (If using phyllo dough, roll up and seal but do not curve. Brush with 2 tablespoons melted butter instead of egg mixture.) Sprinkle with Parmesan.
Bake in a 350 degree F oven for 30 to 35 minutes or until golden. Carefully remove strudel from pan and cool on a wire rack. Just before serving, sift powdered sugar over strudel. Makes 12 to 16 strudel.