Make Chocolate Mousse:In a bowl, whip heavy cream until soft peaks form. Add sweetener, cocoa powder, vanilla, and salt. Continue whipping until thick and fluffy. Refrigerate while preparing peanut butter layer. Make Peanut Butter Cream:In a separate bowl, beat cream cheese until smooth. Add peanut butter and sweetener. Mix until creamy. Add heavy cream and beat until light and fluffy. Layer:Spoon chocolate mousse into small dessert glasses. Add a peanut butter layer. Repeat layers once more. Top with whipped cream or chocolate shavings. Chill 30–60 minutes before serving