Step 1: Preheat your oven to 350°F (175°C). This step is crucial for achieving that perfect rise for your mini bundt cakes.
Step 2: Grease your mini bundt cake pan with non-stick spray or butter to ensure easy removal after baking.
Step 3: In a large mixing bowl, whisk together the flour, cocoa powder, baking powder, baking soda, salt, and sugar until well combined.
Step 4: In another bowl, combine the egg, milk, vegetable oil, and vanilla extract. Whisk until smooth.
Step 5: Pour the wet ingredients into the dry ingredients and mix until just combined. Then, add the boiling water to the batter and stir gently.
Step 6: Pour the batter into the prepared mini bundt pan, filling each mold about two-thirds full. Bake for 15-18 minutes or until a toothpick comes out clean.
Step 7: Remove the pan from the oven and let it cool for about 10 minutes before inverting onto a wire rack to cool completely.
Step 8: In a microwave-safe bowl, combine the condensed milk, chocolate, butter, and vanilla extract. Heat in the microwave until melted and smooth.
Step 9: To assemble, place a mini chocolate bundt cake on a plate, top with ice cream, and drizzle with hot fudge sauce.