Add chopped chocolate to a heat safe bowl

Add 80 mL heavy cream into a saucepan. If using the vanilla bean, split open scrape the beans, and add both beans and whole pod into the heavy cream. If using vanilla paste, just add the cream.

Heat cream over medium heat until it just starts to simmer. Take off heat and remove pod (if using) and pour the heated cream over the chocolate. Let sit covered for a minute until chocolate is melted and then whisk until silky. Let mixture cool for 5 minutes before slowly adding in the remaining 1 cup of heavy cream and whisking until everything is incorporated.

Cover and chill for a minimum of 4 hours or overnight.

After chilling, add in the vanilla extract and/or paste, then beat with an electric mixer or stand mixer with whisk attachment until fluffy. You want the mixture to be airy and stiff so that it is stable.

In a large mixing bowl, whisk the flour, sugar, and salt. Add the cold butter and cut it into the flour mixture using a pastry blender or by pressing it together with your fingers until it resembles coarse breadcrumbs. In a small bowl, whisk to combine the egg and vanilla. Add it to the flour mixture and stir and knead to combine.

Turn the dough out onto a floured surface. Knead 3 to 5 times to bring it together into a cohesive ball. Flatten it into a disc shape, about 1 inch thick, and wrap it with plastic wrap. Refrigerate for 1 hour or freeze for 30 minutes.

To roll-out the crust, place the crust on a well-floured surface and sprinkle flour all over the top. WIth a rolling pin, roll the crust into an 11-inch circle, about ⅛-inch thick. If it starts to crack when rolling, cover it and let it sit for 5 minutes, and try rolling it again.

Place crust in a 9-inch or 10-inch tart pan. Press the crust into the corners and sides of the pan. (If the crust cracks or breaks, you can press it back together or press a piece of excess crust into any holes.) Trim any overhang at the top rim of the pan. Refrigerate the crust for 1 hour or freeze it for 30 minutes.

To parbake: Preheat the oven to 375°F. Prick the bottom of the crust 8 to 10 times with the tines of a fork. Line the crust with parchment paper and fill with pie weights. Make sure the weights fill up to the top of the pan. Bake for 12 minutes. Remove the pie weights and bake another 8 to 10 minutes, until the crust looks dry and lightly golden.

Combine pistachios, softened butter, caster sugar, eggs, and vanilla into a medium mixing bowl and beat until combined

Let crust cool for 10 minutes before adding frangipane. Smooth the top until it's even

Reduce oven temperature to 350

Bake 35 to 40 minutes until it's starting to brown on the edges and it's no longer jiggly. If tart is browning too quickly, you can tent it while it continues to bake. Let cool completely on a rack