How to Make It
In an electric mixer, beat the butter with the sugar and salt until creamy. Beat in the egg yolks, lemon zest and vanilla. On low speed, beat in the flour, 1 cup at a time, until just combined. Divide the dough into 4 equal pieces and flatten them into smooth disks. Wrap separately in wax paper and refrigerate until firm, at least 30 minutes, or for up to 2 days; or freeze for up to 1 month.
Preheat the oven to 350°. On a lightly floured surface, roll 1 disk of the dough 1/8 inch thick. Using cookie cutters, cut the dough into star and moon shapes. Use mini cutters to stamp out patterns in half of the cookies and decorate with dragées. With a metal spatula, transfer the cookies to a large cookie sheet lined with parchment paper. Bake for 15 to 20 minutes, until pale golden. Let the cookies cool on the parchment, then transfer to a rack to cool completely. Repeat with the remaining disks.
Spread a rounded teaspoon of jam on each of the solid cookies and top each with a decorated cookie.