Crust: Mix crust ingredients in a 9-inch springform pan. Press down to form crust.
Stabilized Whipped Cream: In a small pan, combine gelatin and cold water; let stand until thick. Place over low heat, stirring constantly, just until the gelatin dissolves. Remove from heat; cool (do not allow it to set). Whip the cream with the powdered sweetener until slightly thick. While slowly beating, add the gelatin to whipping cream. Whip at high speed until stiff. Set aside.
Filling: Mix cream cheese, sweetener, vanilla, and peanut butter in a large bowl with an electric mixer until well combined. Gently fold in stabilized whipped cream. Pour filling over crust and smooth top with a rubber spatula. Refrigerate at least 4 hours or until firm. Run a knife along the edge of the cheesecake in the pan, then remove the springform side.
Chocolate Ganache: Melt butter and chocolate in a small saucepan or microwave. Stir in powdered sweetener and vanilla. Drizzle chocolate sauce over the top of the cheesecake.