In a large mixing bowl, combine the flour and salt. Cut in the shortening until it resembles pea-sized chunks.

Using a fork, make a little well in the side of the pastry and pour in the water. Use the fork to blend the flour mixture and water together, until it just comes together in a soft, shaggy dough. (Do not over-mix.)

Combine the blueberries, sugar, juice, and zest (if desired) in a medium heavy-bottomed saucepan.

Bring the mixture to a boil, stirring occasionally, and cook for 2-3 minutes.

In a small glass bowl, combine the cornstarch and water until you have a smooth paste; slowly pour the cornstarch into the hot blueberry mixture, stirring while you add it, until well combined. Cook 2-3 minutes more, or until the mixture is thick, dark, and clear.

Remove from heat. Pour the finished filling into a heat-proof glass bowl, and cover with plastic wrap set directly on top of the filling to cool.* Set aside.

On a surface dusted with flour, roll out the pie pastry until about 1/8" thick, rotating as you roll and adding more flour as necessary to prevent sticking.

Using a biscuit cutter, cut the pastry into circles (4" circles for large tarts or 3" circle for minis), and press into muffin tins. Allow to rest at least 1 hours in the fridge.

Prick the tart shells all over with a fork, and bake at 375 degrees Fahrenheit, or until golden brown. Cool on wire racks.

Spoon the prepared tart filling into the baked tart shells. Set aside to cool completely if the tart filling is still warm.

In the meantime, using a zester, zest the lemon into long strips, or cut the rind into small, thin strips with a knife. Put the pieces into a small bowl, sprinkle with sugar, and toss to coat.

Decorate the cooled tarts with fresh blueberries and sugared lemon zest. Serve.

This recipe is best served on the day it is made.