Preheat the oven to 350 degrees F. Place the tart shells on a baking sheet and cook until golden brown, about 15 minutes. Cool to room temperature on a baking rack, and then remove from foil. Place whipping cream in a small pot and bring to a boil. Stir in chocolate and liqueur and mix until chocolate is melted and well incorporated. Spoon the ganache into the tart shells and cool at room temperature until set. Place jam and water in a small pot and cook over medium heat until jam is melted, and then reserve on low heat. Decorate tops of the tarts with mandarin orange segments and dried cranberries. Brush or drizzle top with apricot jam mixture to glaze. Store the tarts in the refrigerator, up to a day, until ready to serve. Garnish each tart with a mint sprig, if desired, before doing so.