This is just chocolate and water, melted and whipped as it cools. And you literally cannot screw it up. Because if you do, you just remelt and start again.
I found this made a great consistency frosting on cupcakes. It was VERY chocolatey because there was nothing to cut the flavor and it held it's shape beautifully.
Two Ingredient Chocolate Mousse
Adapted from Serious Eats
350 grams dark or milk chocolate, chopped
270 grams water
Cold water and ice, for ice bath.
"Put equal parts water and ice into a medium bowl for the ice bath.
Boil the water in a saucepan, or in the microwave, and pour it into a second medium bowl.
Add the chopped chocolate and stir with a spatula or whisk until all the pieces are melted, about 2 minutes.
Place the bowl with the chocolate over the ice bath and whisk vigorously. Continue to whisk until the mixture has the consistency of stiffly whipped cream, and then quickly divide it between individual serving cups or into a serving bowl. Refrigerate."