Check out this instructable for the recipe for the cake: https://www.instructables.com/id/Fiery-Pumpkin-Bread-Cake/
(Or alternatively watch the video here:
Step 1: Prepare the Ingredients
Tempered Dark Chocolate (melt the chocolate until about 3/4 melted then stir together until all has melted. If it isn't 'liquid' enough, add a teeny tiny bit of coconut oil. Whatever you do don't add water!)
Chopsticks (or a fork, or small tongs, or long clean tweezers... Whatever you have)
A piping bag or ziplock bag (piping bags are a bum to clean to I'd actually recommend the ziplock bag, just make sure it's not a thin one that'll pop when you press it - and reinforce the tip with some tape)
A N°1 tip (or cut a really minuscule hole in the corner of the ziplock bag).
Step 2: Preparing the Cupcake Nests
1) Poke some holes in the cupcakes, I just used the tip of the piping bag but you could also use the back of a spoon or even your pinky.
2) Nestle a nut in each hole, like a chick in its nest.
3) Do the same on all the cupcakes. These are the spider's bodies, so make sure to leave enough room for their long spindly legs, but besides from that go crazy. Or be reserved. You're the boss.
Step 3: Lucky Dip
Using your chopsticks (or whichever utensil you elected as your weapon of choice), pick up a nut. Like the ninja you are, carry the nut (lets call him Larry) - carry Larry over to the bowl of dark chocolate. Then when he's not expecting it, dunk Larry in. Make sure he's completely covered in chocolate. Don't worry, he loves it.
Then after all that excitement, place Larry back in his hole and repeat with his buddies.
Step 4: Patience Is a Vertue...
When putting the nuts back in their holes, some chocolate my bubble over the sides a little. Simply wipe off the excess with a kitchen towel (or the tip of your chopstick, just please refrain from licking - that can wait till later. Except of course if you're making these for yourself, then go ahead and do as you please). Then let the chocolate set a little. You can speed up the process by placing them in the fridge for 10' or so.
Step 5: When Larry Got His Legs
Pour the rest of the chocolate bath into the piping bag/ ziplock bag with the N°1 tip or really small hole. Test it to make sure it all flows nicely, then off you go and give a butterfly its wings... no wait, give a SPIDER ITS LEGS. Nice.
Uhm, Larry would like me to remind you that spiders have eight, that's 8, glorious legs. Not six. Please don't embarrass him in front of his friends. Halloween is a very important occasion for him, he needs all of his legs. Thank you.
Step 6: Talking About Friends
Don't forget to give Larry some friends. It's also more fun if you can share this with friends. Who likes to eat cake on their own?
Fine. I like to eat cake on my own. But I LOVE to eat cake with my friends. Somehow it tastes better.
Step 7: HAPPY HALLOWEEN
Or spooky Halloween. I'm not sure what the correct form of greeting is.