Mix the butter with the flour and salt in a bowl using a pastry cutter or knife, or do it in the food processor.

Add a small amount of ice cold water a tablespoon at a time until it just all comes together. Use the least amount of water possible to avoid a heavy soggy dough and maximum flakiness.

Wrap the dough in plastic and chill the dough in the freezer for 30 minutes.

Roll out the dough between sheets of wax paper or plastic to keep from sticking.

Carefully transfer to a drop bottom fluted tart pan (or other tart pan) and trim the edges.

Preheat the oven to 375 degrees F. Prick the bottom of the tart shell all over with a fork and chill in the freezer while the oven preheats.

Bake for 20 to 25 minutes, remove from the oven and cool completely.

Next, in a large bowl combine the blueberries, lemon zest, corn starch, sugar and optional rose water and combine thoroughly with a spoon.

Add the berries to the tart shell and place back in the oven. Cook with berries inside for 60 minutes.

Remove and let cool.