The day before, make the sugared cranberries: simmer water and 1/2 cup sugar until dissolved, cool slightly, then soak cranberries in the syrup for 10 minutes.

Drain the cranberries, toss them in the remaining 1/2 cup sugar until coated, and let dry on a rack for at least 1 hour, until the sugar forms a crisp shell.

Beat cream cheese, powdered sugar, and vanilla until smooth and no lumps remain, about 2 minutes.

In a separate bowl, whip the heavy cream to stiff peaks, about 3 minutes, then fold it into the cream cheese mixture in two additions.

Spread the filling into the cooled tart shell in an even layer, smoothing the top with an offset spatula.

Refrigerate the tart for at least 2 hours, until the filling is firm enough to hold a clean slice.

Just before serving, brush the warmed marmalade lightly over the filling for a glossy finish.

Arrange sugared cranberries over the top in a loose pile and finish with torn gold leaf.