1. Line bottom of 9-inch springform pan with nonstick aluminum foil or regular foil coated with nonstick cooking spray.
2. In large saucepan, heat 1/2 cup heavy cream over medium-high heat until small bubbles appear around edge. Remove from heat. Add chocolate and the 1/3 cup peanut butter; let stand 1 minute. Whisk until smooth. Stir in cereal until evenly coated. Spread half the mixture (about 2 cups) into bottom of prepared pan.
3. In large bowl with electric mixer, beat together cream cheese, the 1-1/2 cups peanut butter, confectioners sugar and vanilla until smooth. In small bowl, beat remaining 1 cup heavy cream until stiff peaks form; fold into cream cheesepeanut butter mixture. Spread evenly over top of chocolate-cereal mixture in prepared pan.
4. Carefully spoon remaining chocolate-cereal mixture on top of peanut butter mixture to make an even layer. Refrigerate overnight to firm.
5. To serve, remove side of springform pan. Invert torte onto waxed-paper-lined baking sheet. Remove and discard foil. Place serving plate on top; invert, right side up. Serve chilled. To cut, use a serrated knife in a sawing motion to avoid cracking the top layer. Makes 16 servings.