In a medium mixing bowl, add chopped chocolate.
In a saucepan, add the 100g Silk heavy whipping cream, Just Egg, and vegan butter. Heat on low until the mixture just begins to curdle, then turn off heat.
Pour the mixture into the bowl with the chopped chocolate.
The cream mixture and chocolate sit for about 1 minute to allow the chocolate to melt. Then stir until well-combined. Cover and set aside until completely cooled. This chocolate ganache.
Using an electric mixer, whisk the whipping cream for about 3 minutes in a mixing bowl until thick and light.
Continue whisking and stream in the chocolate ganache. Continue mixing until well-combined, scraping down the sides of the bowl as necessary.
Cover and place in the fridge until thick and set (about 4 hours). You can also pour the mixture into the dishes you plan to use to serve the mousse in, for a more polished look. This would also reduce the time it takes the mousse to set.