http://juliasalbum.com/2014/05/blackberry-tart-recipe/
Start with
http://juliasalbum.com/2012/09/how-to-make-sweet-tart-crust-dough-from-scratch-flaky/
and do the pre-bake for 20-25 min.
Then TURN DOWN the oven.
Skip the shaved butter on top of the berries. Also; reserve 1.5 cups of berries for the top, rather than 1 cup.