Preheat oven to 350 degrees. Line muffin tins with cupcake liners.

Cupcakes: Combine flour, sugar, and salt in a large mixing bowl. Melt butter in a saucepan, add cocoa and stir together. Add boiling water to saucepan, allow to boil for 30 seconds, then turn off heat. Pour over flour mixture and stir lightly to cool. In a separate bowl, combine buttermilk, beaten eggs, baking soda, and vanilla, then stir into flour/chocolate mixture until combined. Pour batter into lined muffin tin. Bake regular sized cupcakes for 18-20 minutes and mini cupcakes for 10-12 minutes. The cupcakes are done when an inserted toothpick comes out clean. Cool completely on a wire rack, keeping them in the muffin tin for the first 5 minutes.

Frosting: Cream softened butter with an electric mixer. Add cocoa, vanilla, and powdered sugar. Blend until fully combined and creamy. Use milk to thin frosting to desired consistency.

Decorations: Frost cooled cupcakes and cover with sprinkles. Assemble eyes by cutting marshmallows in half and placing Reese's Pieces or chocolate chips in the center of each marshmallow half. Attach eyes and nose with frosting. Cut liquorish to desired spider leg length (I used about 1/3 length of a pull and peel liquorish per leg). Make eight small holes using a toothpick where you want the spider legs to be and insert liquorish into these holes. Happy Halloween!