Whisk the flour, baking powder, and salt in a medium bowl.
Beat the butter and both sugars in another medium bowl with an electric mixer on medium-high speed until light and fluffy, about 30 seconds. Add the egg yolks, vanilla and orange zest mixing until fully incorporated. Slowly add the flour mixture, and continue beating until the dough comes together, stopping and scraping down the sides of the bowl as needed.
For rolled cookies: Roll about a tablespoon of dough by hand into a ball. Dip 1 side of the balls into some coarse sugar and place them sugar-side-up on an ungreased baking sheet, leaving about 1-inch between cookies.
For sliced cookies: Divide dough in half, roll by hand into 2-inch-wide logs, wrap in plastic wrap and refrigerate until firm, at least 2 hours.
Cut the logs into 1/4-inch-thick cookies and place them on ungreased baking sheets, leaving about 1-inch between cookies.
For cutout cookies: Divide dough in half, pat into disks, wrap in plastic wrap and refrigerate until firm, at least 2 hours.
Roll dough between lightly floured parchment, or waxed paper, until about 1/3-inch thick. Transfer sheets to a baking sheet and refrigerate until firm, about 30 minutes. Cut into desired shape using a cookie cutter, place them on ungreased baking sheets, leaving about 1-inch between cookies. (Gather the dough scraps together, pat into a disk, chill and reroll.).
Refrigerate cookies while preheating the oven to 375 degrees F, for at least 30 minutes.
Bake the cookies, until the bottoms are golden, about 10 to 15 minutes depending on shape. Cool on sheets until firm enough to transfer to a rack to cool. Decorate as desired and serve, or store in an airtight container at room temperature for up to 1 month.