Whisk together flours, baking soda, baking powder and salt in a bowl. Set aside.

Using a mixer fitted with paddle attachment, cream butter and sugars together until very light, about 5 minutes. Add eggs, one at a time, mixing well after each addition. Stir in the vanilla. With speed on low, add the dry ingredients and mix until just combined, 5 to 10 seconds. Mix in the 16 oz chocolate chips. Cover the dough with something airtight and refrigerate at least 2 hours, preferably overnight.

When ready to bake, preheat the oven to 350 F. Line a baking sheet with parchment paper or a silicone mat.

Using a cookie dough scoop or an ice cream scoop of medium size, scoop the cookies onto the prepared tray, 6 per sheet. I was aiming for 2 tablespoons of dough per cookie.

Press 3-4 (depending on size) couverture wafers or larger chips into cookie dough ball. Try to separate them as much as possible so you will have room for your spider legs.

Sprinkle the cookies with sea salt if desired and bake until golden brown but still a little soft, about 12-15 minutes. Transfer the baking sheet to a wire rack.

Melt the remaining cup of chocolate chip until stirred smooth (I prefer 30 second increments in the microwave at 50% power). Let cool for a moment or 2.

Trim the tiniest corner off of a plastic bag and insert a tiny circular decorating tip. Scrape the melted chocolate into the plastic bag.

Carefully squeeze the chocolate out the decorating tip to draw lines onto the spider bodies. We went with 6 legs even though it was inaccurate to save space!

Let the cookies cool completely either on the cookie sheets or on a cooling rack. Be certain the chocolate legs have hardened and set before layering the cookies in an airtight container.