Prep Time 1 hr 10 min Total Time 3 hr 5 min Servings 42

1 In large bowl, beat butter, powdered sugar, egg and orange peel with electric mixer on medium speed, or mix with spoon. Stir in flour, baking soda and cream of tartar.
2 Divide dough into thirds. Tint one portion orange and one portion yellow; leave remaining portion plain. Flatten each portion into a disk. Wrap in plastic wrap; refrigerate 20 minutes.
3 On separate sheets of lightly floured waxed paper, roll each portion of dough into 12x9-inch rectangle. Place orange rectangle on top of yellow rectangle, using waxed paper ends to help flip dough over. Top with plain dough rectangle. Starting on a long side, and using waxed paper as an aid, roll dough into a cylinder. Wrap in plastic; refrigerate 1 hour.
4 Heat oven to 375°F. Cut dough into 1/4-inch slices. On ungreased cookie sheet, place slices about 1 inch apart. Sprinkle with coarse sugar.
5 Bake 7 to 8 minutes or until edges are set. Cool 1 minute; remove from cookie sheet to cooling rack.

Expert Tips
For a fun look, turn these into lollipop cookies. Before baking, place paper lollipop sticks on cookie sheet and lay bottom of dough slices on top of sticks. Bake as directed in recipe.

When grating the orange, be careful to avoid the pith—the soft white layer between the peel and the fruit—as it can be bitter.