In a mixing bowl, whisk together flour and eggs.
Gradually add in milk and water, stirring to combine.
Add salt, melted butter, cocoa powder, sugar, and vanilla extract. Mix until smooth.
Heat a lightly greased non-stick skillet over medium heat.
Pour or scoop the batter onto the skillet, using approximately 1/4 cup for each crepe.
Tilt the skillet with a circular motion so that the batter coats the surface evenly.
Cook the crepe for about 2 minutes, until the bottom is light brown.
Flip and cook the other side for about 1 minute.
Repeat with the remaining batter, stacking the crepes on a plate.
In a small saucepan, heat heavy cream until simmering.
Pour over chocolate chips and butter in a heatproof bowl. Let sit for 5 minutes.
Stir until smooth and glossy.
To assemble, spread a spoonful of chocolate ganache on each crepe, fold into quarters.
Serve on a black plate and drizzle with additional ganache if desired.