Preheat and prep: Heat the oven to 350°F (175°C). Line a 12-cup muffin tin with cupcake liners. For a smaller size, line a second tin for 2–4 extra cupcakes.

Mix dry ingredients: In a large bowl, whisk flour, cocoa powder, granulated sugar, brown sugar, baking powder, baking soda, and salt until no lumps remain.

Add wet ingredients (except coffee): Whisk in eggs, milk, oil, and vanilla until smooth. The batter will be thick.

Stir in hot coffee: Slowly pour in the hot coffee while whisking. The batter will thin out and look glossy. If using, fold in chocolate chips.

Fill tins: Divide batter evenly among liners, filling about two-thirds full. Avoid overfilling to prevent overflow.

Bake: Bake 16–20 minutes, until the tops spring back and a toothpick comes out with a few moist crumbs. Don’t overbake.

Cool completely: Let cupcakes cool in the pan 5 minutes, then transfer to a rack to cool fully before frosting.

Make the frosting: Beat softened butter until creamy, 1–2 minutes. Add powdered sugar, vanilla, and a pinch of salt. Beat on low to combine, then on medium-high until fluffy, adding cream 1 tablespoon at a time to reach a smooth, spreadable texture.

Color and decorate: Divide frosting into bowls. Tint with gel colors—orange for pumpkins, purple or green for monsters. Pipe or spread onto cupcakes. Add sprinkles, candy eyes, licorice “spider legs,” or gummy worms for a Halloween look.

Optional ganache drizzle: Warm cream to steaming, pour over chopped chocolate, let sit 2 minutes, then stir smooth. Cool slightly and drizzle over frosted cupcakes for a glossy, spooky effect.