Preheat the oven to 400 degrees F and line a baking sheet with aluminum foil. Place the goat cheese in a large bowl and set aside.
In a large stand mixer with the whisk attachment, beat the heavy cream and sugar to a stiff peak (this can also be done by hand.)
Spoon half of the whipped cream into the bowl with the goat cheese and vigorously whisk until smooth. Add the remaining whipped cream and gently fold to combine. Cover and chill in the refrigerator.
Place the blueberries on the prepared baking sheet and roast in 4 minute intervals, shaking the pan at each interval to ensure that the berries roast evenly. They should be nice and roasted after 12-16 minutes.
Spoon the mousse into small bowls and top with the roasted blueberries.
For best results, serve the mousse within 2-3 hours.