Preheat the oven to 350°F (177°C). Line a cupcake pan with 6 liners. Set aside.

In a large bowl, whisk together the flour, cocoa powder, baking powder, baking soda, and salt.

In a medium bowl, whisk together the egg, granulated sugar, brown sugar, oil, and vanilla.

Pour half of the wet ingredients into the dry ingredients, along with half the buttermilk. Whisk for a few seconds. Repeat with the remaining wet ingredients and buttermilk. Stir just until combined; avoid overmixing.

Spoon the batter into the cupcake liners to 1/2 full.

Bake for 18-20 minutes, or until a toothpick inserted in the center comes out clean.

Remove from oven and allow to cool completely in the pan.

With a handheld mixer or stand mixer fitted with a whisk attachment, beat butter on high speed for about 3 minutes or until creamy and lightened in color, scraping down the bowl as needed.

Add confectioners sugar, cocoa powder, 2 tablespoons of heavy cream, vanilla extract, salt and black food coloring.

Beat on low speed until sugar is incorporated. Increase speed and beat for 3 minutes, scraping the bowl several times. Add another tablespoon of heavy cream if needed to thin the frosting.

Frost the cupcakes once cooled, using a butter knife.

Line a baking sheet with parchment paper. Set aside.

In a medium saucepan, mix together corn syrup, sugar, and water. Bring to a boil over high heat, stirring constantly. Once boiling, stop stirring and boil until the mixture reaches 300°F. This is “hard-crack” stage where the candy will be hard when cooled. If you don’t have a candy thermometer, boil for 10 minutes, then pour a tiny amount into cold water and see if it immediately hardens.

Remove the pan from the heat. Working fast, dip the end of a whisk into the pan, then drizzle the sugar to create small round webs on the parchment paper.

Let cool.

Carefully peel the webs from the paper and stand them up on each cupcake.

Place spiders carefully on each web.