Prepare the Sweet Tart crust.

Make the passion-fruit custard (see the Note on the unique consistency of citrus curds):

In the bowl of the bain-marie, whisk together the egg yolks, whole egg, and sugar. Using a paring knife, cut down the center of the vanilla bean and scrape out the tiny black seeds. Add the scraped vanilla bean (or vanilla extract), passion-fruit juice, and salt to the egg mixture. Whisk briskly until the mixture has thickened, doubled in volume, and holds the lines of a whisk, 5 to 10 minutes.

Remove the curd from the heat and pass through a fine-mesh strainer into a bowl. Discard the vanilla bean (or reserve for another time). Place the bowl in an ice bath and let cool until warm to the touch. Thoroughly whisk in the butter.

Bake the passion-fruit tart:

Preheat the oven to 325°F. Pour the passion-fruit curd into the prepared tart shell. Place the tart on a cookie sheet and bake until the custard sets, 10 to 15 minutes. To test if the custard is set, gently tap the tart ring; if the center does not jiggle, the custard is set. If you have made the curd ahead of time and refrigerated it, the tart will need a few extra minutes in the oven to set.

Serving Suggestions:

Serve the tart at room temperature. It is delicious on its own, but whipped cream or crème fraîche and a few raspberries or strawberries make great accompaniments. I also recommend the Basil Ice Cream, Guava Sorbet, or Pineapple-Rosemary Sorbet. You can also use the curd as a filling for mini tartlets, topped with fresh berries and candied zest.