Sift together both flours and 2 teaspoons cardamom in a large bowl; set aside.
Using a mixer, beat the butter, 1 1/4 cups sugar and the salt in a large bowl until light and fluffy. Scrape down the sides of the bowl, then add the egg yolks; mix well. Add the dry ingredients and mix until just incorporated. Mix in the orange-flower water.
Divide the dough in half; place each half on a sheet of wax paper. Using the wax paper, roll each piece of dough into a 12-by-1 1/2-inch log. Wrap tightly and chill until firm, at least 1 hour.
Preheat the oven to 350 degrees. Mix the remaining 1/2 cup sugar and 1/4 teaspoon cardamom in a bowl. Slice one log of dough into 1/4-inch-thick rounds (keep the remaining log refrigerated). Dip the tops of dough rounds in the cardamom sugar and arrange on ungreased baking sheets; bake until golden brown, 12 to 15 minutes. Place the cookies on a wire rack to cool. Repeat with the remaining log of dough.