Preheat your oven to 325°F. Ensure you have a mini muffin pan ready, either sprayed generously with non-stick spray or lined with mini muffin liners.

In a large mixing bowl, whisk together the flour, sugar, baking soda, and salt.

In a medium saucepan, combine the butter, water, and 5 tablespoons of cocoa powder. Bring this mixture to a boil, stirring occasionally.

Once the chocolate mixture is ready, pour it over the dry ingredients and mix until just combined.

Stir in the buttermilk, beaten eggs, and vanilla extract, ensuring a smooth batter.

Using a tablespoon or a small cookie scoop, fill each mini muffin well with the batter. Bake in the preheated oven for 10-12 minutes or until a toothpick inserted comes out clean.

Allow the mini cakes to cool in the pan for about 5 minutes, then transfer them to a wire rack to cool completely.

In a medium saucepan, combine the milk, 1/2 cup butter, and 4 tablespoons of cocoa powder. Heat this mixture until it comes to a boil. Remove from heat and gradually whisk in the powdered sugar until you have a smooth frosting.

Once the mini cakes are completely cooled, spoon or drizzle the frosting over each one. Allow a few minutes for the frosting to set.

Once the frosting has set, your bites are ready to be enjoyed!