Mix flour, salt, pecans and rosemary in a medium bowl. Set aside.

In a separate larger bowl, using a handheld electric mixer, beat butter and sugar together on medium-high until completely blended and creamy, about 2 to 3 minutes, scraping down the sides of the bowl with a spatula. Add vanilla and blend until combined.

Gradually add flour mixture to butter, beating at medium speed. We added about 1/3 of the flour mixture at a time. The dough will be quite thick and won’t seem like it’s coming together. That is totally okay. If it seems particularly dry, beat in a tablespoon of cold water. It still won’t seem like it’s coming together. That is still totally okay.

After 1/2 hour, preheat the oven to 350ºF. Line two baking sheets with parchment paper or silicone liners.

Take dough from fridge and, using your hands, form balls of dough about 1 inch in diameter. This is where you will see the value of chilling the dough; it will form into balls easily, being quite malleable. You can pinch pieces off or add pieces on at will, and it will hold together beautifully.

Place dough balls on lined cookie sheets about 2 inches apart. We got a dozen per cookie sheet. Using a flat-bottomed glass, press the balls to about 1/3-inch thick. The cookie disks may stick to the bottom of the glass, but you can easily twist them off. You can also slightly reshape imperfections and fix cracks in the edge. Wiping the glass on a paper towel occasionally reduces sticking. Some recipes suggest dipping the glass in flour, but we didn’t want to add potential bits of flour on the cookie surfaces.

Bake cookies, one cookie sheet at a time, for 14 to 17 minutes. Shortbread cookies stay pretty pale, only browning slightly around the edges, so don’t overdo. Just keep an eye on the edges.

Cool cookies on cookie sheet for 5 minutes, then transfer them to a cooling rack to cool completely.