Beat first 3 ingredients at medium speed with a heavy-duty electric stand mixer (using the paddle attachment) until blended. Gradually add flour, beating at low speed just until blended. Add pecans, beating at low speed just until blended. Shape dough into 4 (6-inch-long) logs. Wrap each log in plastic wrap; chill 8 hours.
Preheat oven to 350°. Cut logs into 1/3-inch-thick rounds, and place on parchment paper-lined baking sheets.
Bake at 350° for 10 to 12 minutes or until lightly browned. Remove from oven, and sprinkle tops of hot shortbread lightly with kosher salt. Transfer to wire racks, and let cool completely (about 30 minutes).
Pair with: Champagne or Gruet Demi Sec Sparkling Wine.
The unbaked dough can be frozen up to 2 months when wrapped securely with wax paper or plastic wrap and sealed in a zip-top plastic freezer bag. Thaw overnight in refrigerator before baking.