Preheat the oven to 400ºF.
In a small bowl mix together the brown sugar, flour, cinnamon and melted butter.
Sift the flour and salt into a large bowl.
Cut in the shortening and the butter until the mixture resembles coarse crumbs.
Mix the water and vinegar together in a cup. Add the mixture to the crumbs.
Mix together just until the dough is combined and handles well.
Roll out the pastry dough on a lightly floured surface to about an 11x16” rectangle.
Brush the top of the dough with the cinnamon sugar mixture.
Fold the long edge of the pastry into the center and have them overlap slightly.
Then fold the ends in gently to seal.
Place the pastry on a baking tray that you’ve lined with parchment paper.
Sprinkle the top with granulated sugar.
Bake in preheated oven for 20 minutes or until the pastry is golden brown.
Allow the pastry to cool for 15-20 minutes, then serve.
