Preheat the oven to 350°F (175°C). In a mixing bowl, combine finely chopped pecans, flour, sugar, melted butter, and salt. Mix until crumbly.

Press the mixture into the bottom and up the sides of a 9-inch tart pan. Bake for 10-12 minutes until lightly golden. Remove from the oven and let cool.

In another mixing bowl, whisk together the mascarpone cheese, powdered sugar, and vanilla extract until smooth.

Spread the mascarpone mixture evenly over the cooled pecan crust.

In a small saucepan, combine cranberries, water, and granulated sugar. Cook over medium heat until the cranberries burst and the mixture thickens, about 10 minutes.

Let the cranberry sauce cool slightly before spooning it over the mascarpone filling.

Chill the tart in the refrigerator for at least 1 hour before serving. Slice and enjoy!