In a medium saucepan over low heat, combine the maple syrup and granulated sugar. Cook both over low heat for 7 minutes, stirring every once in a while. Stir in the butter and cook for an additional 2 minutes, continuing to stir every 30 seconds. Stir in heavy cream and salt and, stirring continuously,  cook for an additional 5 minutes.  The Caramel is done when it becomes thick and coats the back of a spoon. Allow it to cool slightly before transferring to a jar or bowl

In a bowl cream together butter and sugars and maple extract as you would for cookies until light and fluffy. Stir in the egg, then fold in the flours. Shape into a ball, cut in half and shape each half into a disk. Shape each portion into a round flat disc. For this recipe, you only need one of the portions, which you now place in the fridge for at least 30 minutes. Put the other half in the freezer and store it there for up to 3 months.

Roll out dough with a floured rolling pin into a 13-inch round on a lightly floured surface and fit into tart pan. Trim excess dough, leaving a 1/2-inch overhang, then fold overhang inward and press against the side of the pan to reinforce edge. Lightly prick bottom and sides with a fork. Chill in the freezer while you preheat the oven to 375°F. Line tart shell with foil or parchment paper and fill with pie weights. Bake in middle of oven until pastry is pale golden along rim, 20 minutes. Carefully remove foil and weights and bake until pale golden all over, 10 minutes more. Cool in pan on a rack.

Cover the bottom of the cooled tart with the caramel. Save a bit of the caramel sauce for decoration. Put tart in the fridge and make the filling.

For the filling, soften the cream cheese by beating it with an electric mixer. Combine the white chocolate and 1 tbsp of the whipping cream in a metal bowl and place this mixture over a hot water bath. Heat up just to the point of melting and take it off the heat. You want this chocolate mixture as close to room temperature as possible to allow for a smooth filling. 

In a bowl whip the cream, icing sugar, maple and vanilla extract to firm peaks. Now, slowly beat in the softened cream cheese, only one spoonful at a time and whip until combined before folding in the room-temperature melted white chocolate.

Pour the filling into the prepared crust and spread evenly. Chill the tart for several hours or overnight before garnishing it with more caramel sauce and some whipped cream