Preheat the oven to 350 degrees. Line one muffin tins with cupcake liners and set aside. In a large bowl, combine flour, sugar, cocoa powder, salt, baking soda, and baking powder. Mix well.
Add in vanilla, eggs, buttermilk, and vegetable oil mixing until smooth. Pour in hot water and mix well. Batter will be very thin.
Pour batter into prepared cupcake liners, about ⅔ full. Bake in a preheated oven for 16-18 minutes, or until a toothpick inserted in the center comes out clean. Allow to cool completely on a wire rack.
Top the cooled cupcakes with frosting, then sprinkle each one with mini marshmallows, chocolate chips, and crushed candy canes. Add a candy cane handle by inserting the hook end of the candy cane into the top-side of each cupcake. Enjoy soon after decorating.