Place the chocolate into a medium glass or metal bowl and set aside. In a small saucepan set over medium-low heat, heat the heavy whipping cream, whisking frequently, until the mixture begins to simmer.
Pour the simmered cream into the bowl of chocolate and cover with a plate for 2 minutes. Remove the plate and whisk the mixture together until it's uniform.
Cover the surface of the ganache with plastic wrap and refrigerate until it's set but still soft, 1-2 hrs depending on how deep your dish is (the shallower the dish the less time it takes) . If you plan on refrigerating for longer, bring it back to room temperature before moving on to the next step.
Remove the plastic wrap and whip with a hand mixer (or in the bowl of your stand mixer with the whisk attachment) for 1-2 minutes, until smooth and fluffy.