Preheat oven to 350 degrees and prepare a baking sheet with parchment paper. Set aside.
In a large bowl, cream together butter and sugar until light and fluffy.
Next, add egg, milk and vanilla extract. Mix to combine.
Add flour, cocoa powder and salt to a smaller bowl and combine. Slowly add dry ingredients into wet ingredients and mix until cookie batter forms.
Shape dough into 1-inch balls and place gently on lined baking sheet. Press down slightly in the center of each cookie, creating a small indent of about half an inch wide.
Add a maraschino cherry in the indent of each cookie.
Bake for 9 to 11 minutes and allow to cool.
Melt candy in a microwave-safe bowl by microwaving in 30 second intervals, stirring between each interval.
Scoop melted candy into a piping bag and drizzle over on top of each cookie. Allow to set before serving.