Combine first 4 ingredients in a large bowl; cut in shortening with a pastry blender until mixture is crumbly. Add milk, stirring just until dry ingredients are moistened.
Turn dough out onto a lightly floured surface; knead 3 or 4 times. Pat or roll dough to 1/2-inch thickness, shaping into a 12- x 8-inch rectangle.
Bring 2 cups water and next 3 ingredients to a boil in a large saucepan; boil, stirring often, 5 minutes. Remove syrup from heat, and stir in butter.
Combine apple and next 3 ingredients; sprinkle over dough. Roll up dough, jellyroll fashion, starting at a long side; press seam, and pinch ends to seal. Cut into 1-inch slices. Place slices in a lightly greased 13- x 9-inch pan; pour syrup over top.
Bake at 425° for 35 to 40 minutes or until golden. Serve warm; top with whipped cream, if desired.