Brush an 8-by-8-inch baking pan with melted butter, and set aside.
Combine the cookie crumbs, coconut, pecans, condensed milk, chocolate chips and salt in a medium bowl. Use a wooden spoon to stir the mixture until combined.
Transfer the mixture to the prepared pan and press it down into the edges.
Bake until the chocolate melts and the top is lightly golden, about 20 minutes.
Remove from oven. Stir the hot mixture with a wooden spoon to evenly distribute the melted chocolate chips.
Set the mixture aside to cool down enough where you can comfortable handle it with bare hands.
Spread the chocolate sprinkles on a large plate and set aside. Prepare a sheet pan with parchment paper and set this next to the sprinkles.
Scoop out a tablespoon of the warm (not hot!) mixture and shape into a ball, then quickly roll into chocolate sprinkles (pressing down to help them adhere), then place on the prepared sheet pan. Work quickly, as the sprinkles will not adhere to cold brownie bites. Also, be careful not to crush the bites as they are somewhat delicate while they are warm.
Once all of the bites are rolled in sprinkles, take a pretzel stick and break (or cut) it in half. Insert the pretzels into the bites to create the spider legs. Repeat until all of the bites have 4 pretzel legs.
Allow the bites to cool off completely, 30-45 minutes, then use the royal icing to adhere the candy eyeballs to the bites. Set the bites aside so the eyeballs can dry.
These brownie bites will keep for 3 days, if stored in an airtight container. They may become dry and hard after that, so it's best to enjoy them while they are fresh!
*To make the cookies crumbs, simply pulverize a few cookies at a time in a food processor until you reach your desired amount. **You can pulse the pecans in the food processor instead of chopping them by handRecipe adapted from: Food Network
Recipe from In Search Of Yummy-ness https://insearchofyummyness.com/spider-brownie-bites/