Preheat your oven to 350°F (175°C).

In a large mixing bowl, whisk together the all-purpose flour, granulated sugar, unsweetened cocoa powder, baking powder, baking soda, and salt.

In a separate bowl, cream together the softened unsalted butter, eggs, vanilla extract, and milk until smooth.

Gradually add the wet ingredients to the dry ingredients and mix gently until just combined.

Line your cupcake tin with paper liners and fill each about two-thirds full with the batter.

Bake for about 20 minutes or until a toothpick inserted comes out clean.

Allow the cupcakes to cool in the pan for 5 minutes before transferring them to a wire rack.

Beat the softened butter in a mixing bowl, adding powdered sugar, heavy cream, vanilla extract, and black food coloring until smooth.

Frost the tops of the cooled cupcakes generously with the black frosting.

Decorate with candy eyes and chocolate bones or pretzel sticks, adding red gel food coloring for a gory effect if desired.