Pre-heat oven to 350 degrees and line two baking sheets with parchment paper or Silpat.
If you're using regular butter, start by clarifying it. Melt butter in a small saucepan (don't stir). Remove saucepan from the heat and let butter sit for about 5 minutes before skimming off the foam on top. Then, pour ½ cup of the yellow liquid into a separate bowl, making sure to leave the remaining milk solids at the bottom of the pan.
In the bowl of a stand mixer or in a large bowl with a hand mixer, combine flour, baking soda, and salt. Mix in corn syrup, ½ cup clarified butter, and vanilla just until dough comes together.
Remove dough from bowl, form into a flat disk, and wrap with plastic wrap. I like to flatten my dough as much as I can in the plastic wrap so it makes it easier to roll. Chill in fridge for about 20 minutes.
Once chilled, roll dough out on a lightly floured surface into a large round about 1/″4 thick. With a 2 ½″ round cookie cutter, biscuit cutter, or drinking glass, cut out rounds. Use a smaller round (like a pastry tip) to cut holes in the center of each round. Gather remaining dough and re-roll into another round. Repeat until all dough is used. Place rounds on prepared baking sheets. Poke holes in cookies with the tines of a fork.
Bake for 7-9 minutes, until cookies are starting to turn golden. Let cookies cool in pans for a few minutes before moving to racks to cool completely.
Place chocolate in a medium heat-proof bowl set over a saucepan of simmering water (or use a double boiler). Stir chocolate occasionally until it is fully melted (see notes for tempering).
Dip each cooled cookie into the melted chocolate and place on a parchment-covered cookie sheet to dry. After all cookies have been dipped, fill a pastry bag, plastic bag, or squeeze bottle with remaining chocolate and draw stripes over each of the cookies.
Let chocolate dry completely before eating (you can chill in fridge to dry faster). Store cookies in airtight containers.