In a large mixing bowl, whip the heavy cream until soft peaks form. You’re looking for that pillowy texture, not butter.
In a separate bowl, stir together the peanut butter, powdered sugar, and vanilla until smooth and slightly glossy.
Fold the whipped cream gently into the peanut butter mixture — don’t overmix, or you’ll lose that dreamy fluff.
Spoon the mousse into serving glasses and chill for at least an hour. Longer is better, but who are we kidding?
Top with crushed peanuts or a dash of chocolate right before serving if you're feeling extra.