Heat the cream in a medium saucepan, over medium-high heat until bubbles begin to form around the edges. Add in the chocolate, and stir with a wire whisk until all of the chocolate is melted and the mixture is smooth and well combined. Stir in the vanilla.
Taste the mixture, and if the chocolate is a little too bitter you can add some caster or icing (confectioner’s) sugar until it’s as sweet as you want it.
Pour into a large heatproof bowl or jug, and leave to cool to room temperature (you can speed this up by placing the bowl into a water bath – simply 1/4 fill the sink with cold water, add some ice and place the bowl of chocolate cream into the sink. Stir the mix regularly to speed cooling). Refrigerate until very well chilled (at least several hours or overnight). I’m not gonna lie, if you’re in a hurry you can chill it quicker in the freezer. Go on, I won’t judge you. Just don’t let it actually freeze.
Whip the chocolate cream with an electric hand mixer until stiff peaks form. It won’t take very long. Pipe or spoon into glasses or small bowls. You can serve it immediately or store in the fridge for several days.