The day before you want to make the dessert place the coconut milk can in the fridge overnight, these is a crucial step as the coconut cream has to harden and separate from the coconut water.
Preheat oven to 325F.
Adjust oven rack to lower middle position.
Grease a donut pan with butter and set aside.
In the bowl of an electric mixer fitted with wire whip attachment, beat eggs at medium speed for about 5 minutes.
Meanwhile, melt chocolate and butter in a large heat-proof bowl set over a pan of almost simmering water, until smooth and very warm, stirring occasionally.
Fold 1/3 of egg foam into chocolate mixture using a rubber spatula until only a few streaks of egg are visible; fold in half of remaining foam, then last of remaining foam, until mixture is totally homogenous.
Transfer batter into the prepared donut pan; fill only 3/4 as the donuts will rise.
Bake until donuts have risen slightly, edges are just beginning to set, a thin glazed crust has formed on surface, and an instant read thermometer inserted halfway through center of cake registers 140 degrees, 25 minutes.
Remove pan from oven and set on wire rack; cool to room temperature.