-Rub half the zest with your fingers into the sugar in a small bowl and set aside. With the paddle attachment (or using a hand mixer), beat the butter at medium speed until it is smooth and creamy. Add both sugars and salt and continue to beat one minute more. You don't want to beat air into it to make it fluffy, but want it nice and creamy.
- Reduce to low and beat in the egg yolks until blended. Add flour and the remainder of the zest and briefly pulse your mixer about 5 times at low speed. If you still see flour on the surface of the dough, pulse a couple of more times. You want to mix just enough to incorporate the flour into the dough. It should be a uniform, clumpy, soft dough.
- Scrape it out onto a floured surface, pat it into a ball, and divide in half. Gently flatten each piece into a oblong shape about an inch thick and chill for at least 2 hours. You can also freeze for a later.
- Preheat oven to 350.
-Transfer dough to a lightly floured work surface. Roll out to a generous 1/8 inch thick. Using a 2 1/4-inch round fluted cutter, cut out wreaths. Re roll scraps, and cut out. Cut out centers of wreaths using a 7/8-inch round cutter.
-Space 2 inches apart on baking sheets lined with parchment paper. Refrigerate until firm, about 15 minutes. Bake until just golden, about 12 minutes. Immediately transfer them to a wire rack, carefully so they won't crack. Let cool completely on wire racks.
Stir together confectioners' sugar, lemon juice and vanilla in a small bowl. Dip surface of each cookie in icing, and sprinkle with peanuts immediately. Let set on wire racks.