1. Dough: In the large bowl of an electric mixer, cream the butter at medium-low speed until it is smooth, about 1 minute. Beat in the sugars and salt at medium speed until creamy. Add the egg yolk, then the citrus zests and vanilla, mixing just until mixture is well combined and slightly fluffy, scraping down the sides of the bowl. Lower mixer speed, and gradually add the flour, mixing only until mixture is thoroughly combined.

2. Divide the dough in thirds, and roll out each portion of dough between two sheets of waxed paper to form a circle 10 inches in diameter and 1/8 inch thick. Leaving the dough circles between the waxed paper, stack them on a baking sheet and refrigerate until firm, for at least 2 hours or up to 3 days; or freeze, well wrapped, up to 1 month.

3. Adjust rack to lower third of oven and preheat oven to 325 degrees F. Line two large cool baking sheets with parchment paper.

4. Remove one dough package at at time from the refrigerator. Peel off top waxed paper sheet, replace it loosely on top, and flip the entire package over. Peel off and discard the second sheet of waxed paper.

5. Using a 1½-inch cutter of any shape, cut out shapes in the dough and set them about ½ inch apart on the baking sheets. Bake, one sheet at a time, for 12 to 15 minutes, or until cookies are no longer shiny, just ivory-colored, and feel slightly firm (lightly touch a few). Place baking sheet on a wire rack until cookies are cool.

6. Jelly Glaze: Keep the oven rack in the same position; preheat oven to 140 degrees F. Place the apricot jam and currant jelly in two small saucepans. Simmer on low heat for 2 minutes to evaporate some liquid before decorating cookies. Cool just until warm.

7. Brush warm apricot jam over half of one cookie’s surface. With a clean brush, paint the other half with the currant jelly. Paint the remaining cookies, setting them as you finish about ¼ inch apart on one large clean baking sheet.

8. Sugar Glaze: Mix the sugar and water together until smooth. With a clean pastry brush, paint a thin coating of glaze over the jelly-glazed cookies. The glaze’s consistency should be thin enough that a transparent film covers the jellies. Adjust the consistency by adding 1 teaspoon water at a time if it is too thick or more sugar if it is too thin. Place cookies in preheated oven until glaze is set and dry, about 10 minutes. Place baking sheet on a wire rack to cool for 5 minutes; then, lift cookies with a metal spatula to a rack to cool.

9. Stack undecorated cookies in an airtight metal container and store at room temperature up to 10 days. Store decorated cookies in one layer in a covered foil-lined cardboard container, such as a cake box, at room temperature up to 3 days.