The peppermint cream that fills the chocolate tart crust comes together right on your stovetop so all that requires baking is the wafer cookie crust. Simply chill, top with whipped cream, and sprinkle with crushed peppermint candy.
Preheat oven to 350 degrees F. In a medium bowl stir together crushed cookies and the melted butter; press onto the bottom and up the sides of a 10-inch fluted tart pan with a removable bottom. Bake for 8 to 10 minutes or until set. Cool completely on a wire rack.
In a medium saucepan combine the sugar and cornstarch. Stir in milk, the cut-up butter, and salt. Cook and stir over medium heat until thickened and bubbly; reduce heat. Cook and stir for 2 minutes more. Remove from heat. Stir in vanilla and peppermint extract. Stir in the 1/2 cup crushed peppermint candies just until combined.
Pour filling into cooled crust. Cool on a wire rack for 30 minutes. Place tart on a platter; cover and chill for 4 to 24 hours.
Using a small sharp knife, gently loosen edge of tart from sides of pan; remove sides from pan. Cut tart into wedges. Serve with Peppermint Whipped Cream and, if desired, additional crushed peppermint candies. Cover and store leftover tart in the refrigerator; serve within 48 hours.
Peppermint Whipped Cream
In a medium mixing bowl combine whipping cream, powdered sugar, and peppermint extract. Beat with an electric mixer on medium to high speed until stiff peaks form (tips stand straight).