FOR THE CHOCOLATE CRUST: Preheat oven to 350°F Combine graham cracker crumbs, 1/3 cup Nestle Toll House baking cocoa and 1/4 cup granulated sugar in 9-inch baking plate. Bake for 8-10 minutes. Sprinkle 1/2 cup morsels over bottom of hot crust; let stnd for 10 minutes or until all morsels are shiny. Spread chocolate over bottom and up sides of crust. Cool to room temperature.
FOR THE FILLING: Microwave 2 cups mosels and 3/4 cup cream in large microwave-safe bowl in high (100%) power for 1 minute; stir. Microwave at additional 10-20 second intervals, stirring until smooth. Cool to room temperature.
Beat remaining cream, sugar and vanilla extract in chilled small mixer bowl until soft peaks form. Fold 2 cups whipped cream into chocolate mixture. Spoon into crust; swirl top. Garnish with remaining whipped cream. Refrigerate unitl firm. Garnish with Chocolate Drizzle; let stand a few minutes befroe serving.
FOR THE CHOCOLATE DRIZZLE: Microwave remaining 1/4 cup morsels in heavy-duty plastic bag on high for about 30 seconds; knead until smooth. Cut tiny corrner from bag; squeeze to drizzle chocolate over pie.