Beat 2 cups cream until soft peaks form. Fold in maple syrup mixture. Spoon mousse into large bowl, stemmed goblets or pots de creme. Refrigerate several hous or overnight. Just before serving, whip remaining 1 cup cream with powdered sugar and vanilla until soft peaks form. Sprinkle mousse with gingersnap crumbs. Garnish with whipped cream and maple candies if desired.