Preheat your oven to 350°F (175°C) and line a muffin pan with colorful cupcake liners.

Chop the bittersweet chocolate, place it in a microwave-safe bowl, and heat in 30-second intervals until smooth.

In a bowl, whisk together all-purpose flour, cocoa powder, baking soda, baking powder, and salt until well combined.

In another bowl, cream together unsalted butter and granulated sugar until light and fluffy. Add eggs one at a time, then add melted chocolate.

Gradually incorporate the dry ingredients, alternating with buttermilk and hot water, until smooth.

Fill each cupcake liner halfway with batter and bake for 17-19 minutes. Test doneness with a toothpick.

Let cupcakes cool in the pan for 5 minutes before transferring to a wire rack to cool completely.

Prepare the frosting by beating unsalted butter, then gradually mix in cocoa powder, powdered sugar, heavy cream, and vanilla until fluffy.

Once cool, frost the cupcakes generously, creating a whimsical peak.

Decorate with brown jimmie sprinkles, use pretzel pieces for spider legs, and add candy eyeballs on top.

Serve your delightful Spider Cupcakes and enjoy the festive flavors!