Preheat your oven to 400 degrees F.
In a food processor, combine 1 cup of all-purpose flour, ¼ cup of cold butter, ¼ cup of granulated white sugar, ¼ teaspoon of baking powder, ½ teaspoon of grated lemon zest, 1 pinch of salt, and 1 large egg. Pulse until the mixture resembles coarse crumbs.
Press the dough into the bottom and up the sides of a 9-inch springform pan.
Chill the crust in the refrigerator for 10 to 15 minutes.
Bake the crust for about 10 minutes, or until it’s light golden brown.
In a large saucepan, crush 2 cups of fresh blackberries with the back of a large spoon.
Add ¾ cup of granulated white sugar, 3 tablespoons of cornstarch, and ¼ teaspoon of salt to the crushed berries.
Heat the mixture over medium heat until it thickens and becomes clear.
Once thickened, pour the filling into the cooled crust.
Sprinkle 2 tablespoons of granulated white sugar over the top.
Allow the tart to cool for at least 1 hour before cutting into wedges.
