Using a food processor with dough blade, add in flour, powdered sugar, cocoa and salt. Pulse two times to mix.

Add in vanilla and 1/2 of the cold butter. Pulse several times. Add in remaining butter and pulse until mixture turns into a ball. Scrape down sides of needed. Remove dough and wrap in plastic wrap and chill for 30 minutes.

Turn dough out on a surface dusted with powdered sugar. Roll to a 1/4" thickness.

Cut dough into 1"x3" long strips.

Scrape up any excess dough and roll out again to cut out additional strips.

Bake on a parchment lined baking tray in a preheated 300°F fahrenheit oven for 18 minutes. Let sit on sheet for 1 minute before transferring to a plate.

In a double boiler, melt chocolate and butter.

Dip 1/2 of the shortbread strips in the chocolate.

In a medium sized bowl have nuts ready. Dip 1/4" tip of the chocolate area into finely chopped pecans.

Lay flat on clean parchment lined tray to cool and set.