Beat peanut butter, salt, cream cheese, powdered sugar, and vanilla in a large bowl until smooth.
In a separate bowl, beat the heavy cream and granulated sugar until stiff peaks form. Gently fold the whipped cream into the peanut butter mixture until light and airy.
Transfer the mousse into cups or jars using a spoon or piping bag. Serve immediately or refrigerate for at least 30 minutes for a firmer texture.