CRUST: 2 cups (36 wafers) finely crushed chocolate wafer cookies. (I have also used the chocolate graham crackers)
1/2 cup butter, melted
3 Tablespoons sugar

GANACHE: 1 cup semi-sweet chocolate chips
2/3 cup heavy whipping cream

FILLING: 1 cup powdered sugar
2 (8 oz.) cream cheese, softened
2 teaspoons peppermint extract
1 1/2 cups whipping cream (whipped)
2/3 cup peppermint candies crushed

Combine all crust ingredients in small bowl. Press onto bottom of ungreased 9 x 13 pan. Set aside.
Melt chocolate chips and 2/3 cup whipping cream in 1 quart saucepan over low heat, stirring occasionally, until smooth (4 to 5 minutes). Pour over crust. Place pan in freezer while making filling (at least 10 minutes).
Combine powdered sugar, cream cheese and peppermint extract in large mixer bowl. Beat at low speed, scraping bowl often, until smooth and creamy (2 to 3 minutes). Gently stir in whipped cream and crushed candies. Spread evenly over ganache layer. Sprinkle with additional crushed candy if desired. Cover and freeze 4 hours or overnight. Cut into squares to serve. Serve frozen or at room temperature. Store frozen.