Chocolate Mint Napoleons

Instructions

1. For sauce: Combine creme de menthe and sugar in small saucepan; scrape in seeds from vanilla bean; add bean; stir over medium heat until sugar dissolves; remove from heat; cool; strain into bowl.
2. For mousse: Whisk yolks and 1/4 cup sugar in small bowl to blend; bring 1/4 cup cream to simmer in small saucepan; gradually whisk hot cream into egg mixture; return mixture to same saucepan; stir constantly over medium-low heat until custard thickens, about 1 minute (do not boil); reduce heat to low; add chocolate, creme de cacao and butter and stir until smooth; pour into large bowl; chill until cool, stirring occasionally, about 15 minutes; beat 1/2 cup cream in small bowl to stiff peaks; fold cream into chocolate mixture; cover and chill.
3. For Chocolate Bark: Line 2 large baking sheets with parchment; finely grind mints in processor; place half of chocolate in top of double boiler set over simmering water; stir until candy thermometer registers 115F; pour onto 1 prepared sheet; using spatula, spread chocolate to 1/16-inch thickness over parchment; sprinkle half of ground candies over half of chocolate; fold parchment in half to seal candies in chocolate; repeat with remaining chocolate and candies; cover and chill 1 to 24 hours; peel parchment off chocolate bark; break or cut each sheet of bark into 6 large irregular pieces, reserving any small pieces for garnish; place 1 bark piece on plate; spread scant 1/3 cup mousse over bark; place another bark piece on top of mousse; spread scant 1/3 cup mousse over; top with another bark piece; place dollop of mousse on top of chocolate and top with any smaller bark pieces, standing pieces upright; repeat with remaining bark and mousse; (Can be made 6 hours ahead; cover; chill).
4. Serve napoleons with sauce.