Step 1: Prepare the Tart Crust: Begin by beating the 8 tablespoons of unsalted butter in a stand mixer on medium speed for 1 minute until it’s creamy. Add the 2/3 cup powdered sugar and mix on medium-high speed until pale and fluffy, about 7 minutes, scraping the bowl as needed. Then, mix in the 1 egg yolk, 1/2 teaspoon vanilla extract, and 1/4 teaspoon kosher salt for about 1 minute.

Next, add the 1 cup all-purpose flour and mix on low speed until no dry flour remains, around 1 minute. Form the dough into a disk, wrap it, and chill in the fridge for at least 2 hours or overnight. Once chilled, roll the dough on a lightly floured surface to about 1/8 inch thick and 11 inches in diameter. Press it into a 9.5-inch tart pan, trim any excess, and freeze for 30 minutes.

Preheat your oven to 350 degrees Fahrenheit. Line the tart shell with parchment or foil, fill it with pie weights or dried beans, and bake for 30 minutes. Remove the weights and bake for another 15 minutes until golden. Let it cool completely before moving on.

Step 2: Make the Passion Fruit Curd: In a medium heavy-bottomed saucepan, whisk together the 6 egg yolks, 1 whole egg, 1/2 cup sugar, 1/2 teaspoon vanilla extract, and 1/2 cup passion fruit puree. Heat this mixture gently over medium-low heat, whisking constantly until it thickens, which takes about 7 to 10 minutes.

Strain the mixture to remove any lumps, then stir in the 8 tablespoons unsalted butter cut into 1-inch chunks until smooth. Lower your oven temperature to 325 degrees Fahrenheit. Pour the curd into the cooled tart shell on a baking sheet and bake for 12 to 15 minutes until the center is set with no jiggle.

Allow the tart to cool to room temperature, then top with lightly sweetened whipped cream if you like. The total preparation involves a cook time of 1 hour, plus 2 hours and 30 minutes of chilling time, making the whole process about 3 hours and 30 minutes. For more tips on crusts, check out this Sweet Tart Crust Guide from a reliable source.

Step 3: Finishing Touches and Serving: Once baked, let the tart cool fully for the best texture. If you’re in a rush, pop it in the fridge to speed things up, but room temperature works great too. This is also a good spot to add an internal link; for instance, if you enjoy frozen treats with your tart, try this no-churn ice cream recipe for a perfect pairing.

Adaptations for dietary needs, like using vegan substitutes, keep this recipe flexible. Remember, the key is to enjoy the process and the final result, which combines fresh tropical flavors with a crispy crust for a delightful dessert.