Crust
Put chocolate wafers in a food processor and blend until fine.
Melt butter.
Mix butter and crumbs in a small bowl.
Press mixture into bottom and sides of a 9" x !/2" tart pan with a removable bottom.
Chill for 30 minutes
Pie
Microwave chocolate in microwavable bowl on MEDIUM-HIGH (50%) for 1 to 3 minutes, stirring occasionally until melted and smooth.
Puree tofu in food processor; add melted chocolate and powdered sugar; process until completely blended, scraping sides down. Add vanilla; blend well.
Turn mixture into crust.
Chill 1 hour or until set. Garnish with whipped cream and shavings. Let stand at room temperature for 15 minutes, uncovered, before serving (to enhance the flavor).
Standard Mousse Notes
A standard chocolate mousse requires cooking the egg yolks and chocolate mixture, then beating the egg whites separately and folding them into the cooled mixture. This version requires a minimum of 3 hours to chill. All in all, considerably more effort than this quick tofu method.