While the pastry cream is chilling, make the pastry crust. In a food processor, pulse the flour, arrowroot starch, powdered sugar, salt, and cubed cold butter until crumbly and butter has been combined. Separately, whisk the two egg yolks and vanilla until smooth, then, while pulsing food processor, slowly pour in the cold egg yolks and pulse until the dough comes together in a ball. Scrape out of the food processor and form into a 6-inch flat circle, wrap in plastic wrap, and chill for at least 2 hours.
Once the dough is chilled, remove from fridge and let sit on the counter for a few minutes (10-15) to soften. Then using a floured surface and floured rolling pin, roll out dough into a 12 inch circle and carefully line tart pan with the dough, pressing into the side grooves. Cut off the edges that extend beyond the top of the tart pan. Refrigerate the formed crust again for 30 minutes before baking. While chilling, preheat the oven to 425 degrees Fahrenheit. Once chilled, remove from fridge and poke a series of small holes into the base of the crust with a fork for venting, then bake with pie weights for 15 minutes. Then remove the pie weights, tent the edges of the crust with foil so that they don't get too brown, and continue to bake for 15 minutes until golden (crust should be fully blind baked because you won't be baking the filling). Let crust cool completely before filling.