01 - Cream the softened butter and granulated sugar together in a large bowl until light and fluffy.
02 - Mix in grated orange zest and salt, then gradually add all-purpose flour, blending until a soft dough forms.
03 - Shape dough into a disk, wrap in plastic, and refrigerate for 30 minutes.
04 - Preheat oven to 350°F. On a lightly floured surface, roll dough to 1/4 inch thickness. Cut into rounds or desired shapes and place on parchment-lined baking sheets.
05 - Bake cookies in preheated oven for 12 to 15 minutes or until edges are lightly golden. Transfer to a wire rack to cool completely.
06 - In a microwave-safe bowl, combine chopped semisweet chocolate and vegetable oil. Microwave in 30-second intervals, stirring, until smooth.
07 - Dip half of each cooled shortbread cookie into melted chocolate, allowing excess to drip off. Place on parchment and let set until chocolate is firm.