Preheat oven to 350°F. Line a baking sheet with parchment paper, set aside.
In the bowl of a stand mixer fitted with the paddle attachment, mix butter, egg, sugar, orange zest and vanilla very well (about 1 minutes), scraping the sides at least once.
In a separate bowl, combine flour and salt. Slowly add flour mixture to butter mixture and mix until just combined.
Sprinkle a large clean surface with flour and roll out dough to about 1/4" thickness. Use a cookie cutter or the top of a glass to cut out cookies. (I just use one of our everyday glasses to make circles.)
Bake cookies for 8-10 minutes, until just set, but not browned.
Allow cookies to cool on the cookie sheet for 2 minutes before transferring to a cooling rack.
Finely chop cranberries and mix well with orange zest. Set aside.
While cookies are cooling, pour white or dark chocolate chips into a small microwave-safe bowl. Heat for 30 seconds at a time in the microwave, stirring after each interval, until fully melted. (It always takes me 3 30 second intervals.)
Holding one cookie at a time use a spoon to spread chocolate over half of the cookie and scrape the side to keep the chocolate from pouring down the edge. Sprinkle with cranberry mixture and press gently so the cranberries and zest hang on to the chocolate.
Allow chocolate to fully set (about 10 minutes). Enjoy!!