Heat oven to 350℉ (175℃).
Spray a 9-inch tart ring with cooking spray. Set aside.
In the bowl of a food processor fitted with a dough blade, combine flour, sugar, baking powder, and lemon zest.
Pulse to mix.
Add butter, a few slices at a time, pulsing after each addition.
Add egg and vanilla.
Pulse until it forms a smooth dough.
Turn out onto lightly floured parchment paper.
Roll into a round that is ¼-inch thick.
Transfer dough to prepared pan.
Press to remove air bubbles and to ensure dough is fitted all the way to the edges.
Cut excess dough away from top.
Place a sheet of parchment paper in crust.
Fill with pie weights, making sure they are spread evenly.
Bake for 20 minutes.
Remove from oven.
Carefully remove parchment paper and pie weights.
Return to oven.
Bake an additional 10-15 minutes, until crust is lightly browned.
Set aside to cool.