Preheat your oven to 350°F (177°C) and line a cupcake pan with cupcake liners.

Combine semisweet chocolate chips, dark cocoa powder, and boiling water in a bowl until smooth. In a separate bowl, whisk flour, sugar, baking soda, and salt. Fold in the chocolate mixture, then add oil, eggs, and vanilla.

Distribute the batter into lined cupcake cups, filling about two-thirds full. Bake for approximately 20 minutes, until a toothpick inserted into the center comes out clean.

To make the buttercream, beat room temperature butter until fluffy, then gradually add powdered sugar and heavy cream. Mix until smooth and fold in Oreo crumbs.

For the ganache, heat chocolate chips and heavy cream in a microwave-safe bowl until melted and smooth.

After the cupcakes cool completely, pipe the buttercream onto each cupcake and drizzle with ganache. Garnish with a halved Oreo.