Roll the puff pastry 1/4-inch thick and pierce it all over with the tines of a fork. Line a flan ring with the pastry and chill the ring for 20 minutes.

Preheat the oven to 350 degrees F.

Line the flan ring with parchment paper or coffee filters and fill the shell with pie weights. Bake the pastry shell for about 25 minutes, or until the pastry is golden brown. Remove the shell from the oven and let cool to room temperature. Remove the pie weights.

Distribute the fruit evenly over the bottom of the shell, then pour in the Creme Brulee. Smooth the top with a long-bladed spatula.

Just before serving, heat a caramel iron on the burner of a stove. Sprinkle the sugar evenly over the top and carefully caramelize the sugar with the hot iron. Alternately, place the tart under a hot broiler, near the heat, for 1 to 2 minutes, or until the sugar caramelizes. Or use a small blow torch to caramelize the sugar.

In a large metal bowl set over a bain marie, whisk the egg yolks and sugar together until the mixture is light and thick enough to form a ribbon. This takes quite a long time; be strong and patient. Remove from the heat.

Carefully whisk in the cream. Add the vanilla bean. Place the bowl back over the bain marie and cook slowly for about 45 minutes, stirring frequently. Take care that the water does not boil. The custard will be done when the mixture adheres to your fingers without dripping.

When the custard is done, remove from the heat and whisk in the butter, a little at a time, until all of it has been incorporated. Strain through a fine strainer into a bowl. Chill at least 6 hours or overnight.