Preheat the oven to 350 degrees. Line a mini muffin/cupcake pan with liners, set aside.

In the bowl of a stand mixer, combine the flour, sugar, cocoa, baking soda, baking powder and salt. Whisk to combine.

Add in the oil, milk, water, eggs and vanilla. Mix well, scraping the sides often and thoroughly combine.

Measure out about a tablespoon's worth of batter into each cupcake liner - filling about half full.

Bake in the preheated oven for about 8-10 minutes or until the center is set. Allow to cool completely before decorating.

For the frosting - in the bowl of a stand mixer, combine the softened butter, cocoa powder, salt and about half of the powdered sugar.

Mix on low speed until combined. Add in the vanilla, milk and remaining powdered sugar. Mix on low until combined.

Scrape the sides often. Bump up the speed to medium and whip the frosting for about a minute.

Transfer the frosting to a piping bag fitted with a large star tip.

Pipe a dollop on each cooled cupcake and immediately decorate with sprinkles.