Step 1: Preheat and Prepare: Preheat oven to 350F (175C). Line a 12-cup muffin tin with cupcake liners. This prevents sticking and makes for easy cleanup.
Step 2: Combine Dry Ingredients: In a large bowl, whisk together the flour, cocoa powder, sugar, baking soda, baking powder, and salt. Ensure all dry ingredients are evenly distributed for consistent flavor and texture.
Step 3: Add Wet Ingredients: In a separate bowl, whisk together the buttermilk (or milk and vinegar mixture), oil, and vanilla extract. Combine these wet ingredients ensures uniform consistency.
Step 4: Combine Wet and Dry: Gradually add the wet ingredients to the dry ingredients, mixing on low speed until just combined. Be careful not to overmix.
Step 5: Incorporate Boiling Water: Carefully pour the boiling water into the batter and mix until smooth. The batter will be thin. Boiling water helps bloom the cocoa powder, enhancing the chocolate flavor.
Step 6: Fill Cupcake Liners: Fill each cupcake liner about full. Overfilling can cause the cupcakes to overflow during baking.
Step 7: Bake: Bake for 18-22 minutes, or until a toothpick inserted into the center comes out clean. Baking time may vary depending on the oven.
Step 8: Cool: Let the cupcakes cool in the muffin tin for a few minutes before transferring them to a wire rack to cool completely. This prevents condensation and soggy bottoms.
Optional Tip: For a richer flavor, add 1 teaspoon of instant coffee granules to the boiling water. For a dairy-free option, substitute almond milk for buttermilk and ensure the oil is plant-based.