Place logs on lightly greased large cookie sheet about 4 inches apart. Flatten each log to 2-inch width. Bake for 25 to 30 minutes or until logs begin to crack and edges begin to brown. Let stand 10 minutes on cookie sheet. Reduce oven to 300 degrees.
Place slices on same cookie sheet, cut-side down.
Bake for 20 to 25 minutes, turning once or until crisp and very light brown on both sides. Place on cooling racks. Sprinkle cooled cookies with sifted powdered sugar. Store in a loosely covered jar.