The dough is divided three ways to make these colorful cookies. The result is a dessert that has chocolate, plain, and cinnamon cookie stripes.
Prepare Basic Icebox Cookies recipe. Divide dough into thirds. Stir in unsweetened chocolate, melted and cooled; miniature semisweet chocolate pieces and ground cinnamon into one portion of the dough (knead, if necessary).
Stir in crushed red cinnamon candies into another portion of dough. If desired, tint remaining portion of the dough with a little red paste food coloring.* Cover and chill all dough portions for at least 1 hour or until dough is easy to handle.
On a piece of waxed paper, roll chocolate dough into an 8x4-inch rectangle (keep remaining dough chilled); place waxed paper with dough rectangle on a cookie sheet, dough side up. On another piece of waxed paper, roll cinnamon-candy dough into an 8x4-inch rectangle. Invert cinnamon-candy dough over chocolate dough; peel off waxed paper. On another piece of waxed paper, roll the red-tinted or plain dough into an 8x4-inch rectangle. Invert red-tinted or plain dough onto cinnamon-candy dough; peel waxed paper off top and bottom of dough stack. Press dough portions together lightly. Wrap dough stack in plastic wrap. Chill for 1 hour.
Preheat oven to 375 degrees F. Place dough stack on a cutting board, chocolate side up. Trim edges of dough stack. Cut dough stack crosswise into 1/4-inch-thick slices. Arrange slices 2 inches apart on ungreased cookie sheet. Bake in the preheated oven for 8 to 10 minutes or until edges are lightly browned. Transfer to a wire rack; let cool. Makes about 24.
Paste food coloring gives cookies a better red color than liquid food coloring.
Layer cookies between pieces of waxed paper in an airtight container; cover. Store at room temperature for up to 3 days or freeze for up to 3 months.
In a large bowl, combine shortening and softened butter; beat with an electric mixer on medium to high speed for 30 seconds. Add the sugar, baking powder, and salt. Beat until combined, scraping side of bowl occasionally. Beat in egg and vanilla. Beat in as much of the flour as you can with the mixer. Stir in any remaining flour.