Strawberries, Banana Mascarpone, And Crushed Cookie Parfaits

Ingredients

• 2 dry pints fresh ripe strawberries, rinsed and drained
• 3 tablespoons seedless raspberry or strawberry jam
• 1 tablespoon grand marnier, framboise, or crème de banana liqueur
• 3 large or 4 medium very ripe bananas, chilled
• ¼ cup confectioners sugar, sifted
• 4 tablespoons granulated sugar
• 1½ teaspoons pure vanilla extract
• 2 generous cups mascarpone (2-pound, 2-ounce tub), well chilled
• one 9-ounce box nabisco chocolate wafer cookies, crushed into small pieces
• 2 extra-large ripe but firm bananas for garnish
• mint sprigs for garnish