For this recipe, you may use a hand-held electric mixer or stand mixer with whisk attachment. Preheat the oven to 180C and line a 12-cupcake pan with paper liners.
Mix the flour, cocoa powder, sugar, baking soda, and salt together thoroughly in a large bowl (or stand mixer bowl).
Melt the butter in the microwave, weigh and cut in chunks. Microwave for 15 seconds at a time, we want the butter to just melt, we don’t want to heat it or burn it.
Add to the mixing bowl, the butter, eggs, and vanilla and beat on medium speed for one minute.
Add half of the water and beat for 20 seconds. Scrape the sides of the bowl and add the remaining water. Beat for 20-30 seconds until the batter is smooth.
The batter will be thin enough to pour. Divide it evenly among the lined cups. Bake 18-22 minutes, just until a toothpick inserted into a few of the cupcakes comes out clean.
Set the pan on a rack to cool for 10 minutes. Transfer the cupcakes from the pan to the rack and let them cool completely before frosting or filling. Store and serve at room temperature.