Heat oven to 375℉/190℃.
Line cookie sheets with parchment paper. Set aside.
With an electric mixer, beat butter and sugar until creamy, about 1 minute, scraping down sides as necessary.
Add flour and zest.
Mix only until blended.
Using the heat from your hands, form into a ball.
Roll out on a non-stick surface (marble, parchment, silicone) to 3/16 inch thick.
Cut with 2 inch round cutter.
Place on prepared cookie sheets.
Re-roll and cut remaining dough.
Bake for 10 minutes, until just starting to color.
Allow to cool on pan.