Preheat the oven to 350°F (175°C). Line a muffin tin with cupcake liners.

In a mixing bowl, whisk together flour, sugar, cocoa powder, baking powder, baking soda, and salt.

Add the egg, milk, vegetable oil, and vanilla extract. Mix until smooth.

Pour the batter into the prepared muffin tin, filling each liner about 2/3 full.

Bake for 18-20 minutes or until a toothpick inserted comes out clean. Let cool completely.

In a large mixing bowl, beat the softened butter until creamy.

Gradually add powdered sugar, mixing until combined. Add heavy cream and vanilla, beat until fluffy.

Transfer the frosting to a piping bag fitted with a round tip.

Pipe the frosting onto each cooled cupcake to create a ghost shape.

Use black decorating gel to add eyes and a mouth to each ghost.

Serve and enjoy your spooky ghost cupcakes!