Preheat your oven to 350°F (175°C) and line a cupcake pan with cupcake liners.
In a large mixing bowl, whisk together the granulated sugar, all-purpose flour, Dutch-processed cocoa, baking powder, baking soda, and salt until well combined.
In a separate bowl, beat the eggs, then add the whole milk, canola oil, and vanilla extract. Mix until everything is well incorporated.
Pour the wet mixture into the dry ingredients. Mix gently until just combined, being careful not to overmix.
Carefully stir in the boiling water. The batter will be thin, but that’s perfectly fine! This is what makes the cupcakes moist.
Fold in the semi-sweet chocolate chips until evenly distributed throughout the batter.
Pour the batter into the prepared cupcake liners, filling each about two-thirds full.
Bake in the preheated oven for 18-20 minutes, or until a toothpick inserted into the center comes out clean.
Remove the cupcakes from the oven and let them cool in the pan for 5 minutes before transferring them to a cooling rack to cool completely.
In a large mixing bowl, beat the room temperature unsalted butter until creamy. Gradually add the powdered sugar, mixing until smooth. Then, add the heavy cream, melted chocolate chips, and vanilla extract. Beat until fluffy.
Once the cupcakes are completely cool, use a piping bag to frost them with the chocolate buttercream.
Sprinkle mini chocolate chips on top for an extra touch of chocolatey goodness.