Combine butter, egg and vanilla in large bowl. Beat at medium speed, scraping bowl often, until creamy. Reduce speed to low; add all remaining cookie ingredients. Beat until dough forms a ball.
Shape dough into 2 (10x1 1/2-inch) logs on lightly floured surface. Roll in decorator sugar. Wrap in plastic food wrap; refrigerate at least 1 hour.
Heat oven to 375°F. Roll log into egg shape. Cut into 1/4-inch slices with sharp knife. Place 1 inch apart onto ungreased cookie sheets. Reshape into egg shape, if necessary. Bake for 6 to 9 minutes or until edges are lightly browned. Cool 1 minute on cookie sheets; remove to wire cooling rack. Cool completely. Decorate cookies with decorator sugars and gels as desired.
- For tinted eggs, add 10 to 12 drops food color to dough before shaping into logs.
- Decorator gels are available in small tubes in the baking aisle of the supermarket.
- Cookie dough logs can be frozen up to 2 months. Tightly wrap in plastic food wrap; place into plastic freezer bags. To use, thaw in refrigerator; slice and bake as directed.