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

In a large mixing bowl, combine the flour, sugar, cocoa powder, baking powder, baking soda, and salt. Whisk together until well blended.

In another bowl, mix the vegetable oil, buttermilk, eggs, and vanilla extract. Whisk until smooth.

Pour the wet ingredients into the dry ingredients. Mix until just combined.

Gradually add the boiling water to the batter, mixing until smooth. The batter will be thin.

Divide the batter evenly among the cupcake liners, filling each about 2/3 full.

Bake in the preheated oven for 18-20 minutes, or until a toothpick inserted into the center comes out clean. Allow to cool in the pan for 5 minutes, then transfer the cupcakes to a wire rack to cool completely.

For the ganache, heat the heavy cream in a small saucepan over medium heat until it begins to simmer. Remove from heat and add the chopped chocolate and butter. Let sit for 5 minutes.

Stir the mixture until smooth and glossy. Let the ganache cool slightly until it thickens.

Once the cupcakes are completely cool, dip the tops into the ganache or use a spoon to drizzle it on top. Allow the ganache to set before serving.