Chocolate cranberry tart
For cranberry topping
Pour half of the cranberry juice into a small bowl and sprinkle gelatin over it. Let stand until softened, about 15 minutes.
Combine the rest of the cranberry juice, cranberries, sugar, lemon juice and peel, ginger and salt in medium saucepan. Bring the mixture to a rolling boil, stirring until the sugar dissolves.
Reduce heat to medium and simmer until cranberries become tender. Do not let them pop and make sure the remain plump, about 5 minutes. Strain into bowl and set the cranberries aside.
Add the gelatin mixture to the hot juice in bowl, stirring until gelatin dissolves. Stir the cranberries back into juice. Chill until cranberry mixture is cold and slightly thickened. This will take at least at least 8 hours or leave overnight. This mixture can be made 2 days ahead. Cover and chill.
Stir chopped candied ginger into cranberry mixture.
Position rack in center of oven and preheat to 200 degrees C. Combine chocolate cookie crumbs, sugar, and salt in medium bowl. Add 5 tablespoons melted butter and stir until crumbs feel moist when pressed together with fingertips, adding remaining 1 tablespoon melted butter if mixture is dry. Pour the melted chocolate into the crumbs mixture and stir to coat.
Press crumb mixture firmly onto bottom and up sides of tart pan. Bake chocolate crust for approx. 10 minutes until beginning to set and slightly crisp, pressing with spoon if crust puffs during baking. Transfer tart pan to rack and cool crust completely before filling. Place in the refrigerator for a few hours to allow the chocolate to set.
For mascarpone filling
Using electric mixer, beat all ingredients except ginger in medium bowl just until thick enough to spread. Do not over beat or mixture may curdle. Spread filling in cooled crust. Cover and chill overnight
Spoon cranberry mixture evenly over mascarpone filling. Chill at least 2 hours and up to 6 hours. Cut tart into wedges and serve cold, drizzled with chocolate sauce