For the spiced apple pie filling:
Mix the sliced apples, lemon juice and the brown sugar in a bowl and keep covered for about half an hour.
Then melt the butter in a pan. Put the apple-sugar mixture and the remaining ingredients into the pan and cook over medium heat, till the apples are cooked and the juices have thickened, and the mixture is moist but not runny.
Use in the crostata.
For the pasta frolla:
Put sugar, flour, salt, and lemon zest in the food processor and pulse a few times to mix.
Add the butter and pulse a few times, until the mixture has the consistency of coarse meal. Empty food processor's bowl onto your work surface.
Make a well in the center of the mounded flour and butter mixture and pour the beaten egg into it. Use a fork to incorporate the liquid into the solid ingredients, and then use your fingertips. Knead lightly just until the dough comes together into a ball.
Shape the dough into a flat disk and wrap in plastic wrap. Place the dough in the refrigerator and chill for at least two hours. You can refrigerate the dough overnight.
Take the pasta frolla out of the fridge, unwrap it and cut 1/3 of the dough and divide it into 6 equal portions. Refrigerate this dough while you work on the tart base.
To help roll the crostata dough, keep the dough on top of the plastic wrap that you had it wrapped in. This can help rolling the dough and can also help when transferring the dough to your pan. You can also use parchment paper for this.
After overnight refrigeration, I didnu2019t have problems rolling out my pastry dough. Lightly dust your work surface with flour and start rolling out the dough to about 1/8u201d thickness. Using a 2 1/2u201d or 2 3/4" round cutter, cut out 6 circles. Take the scraps and place on top of each other (do not knead) and then roll out and cut thin strips to use for the lattice in the crostatine.
Now take the 6 pieces of dough in the fridge, and roll each one into rope of uniform thickness. The u201cropeu201d should be long enough to cover the circumference of your dough circles. Wet the edges of the circles with milk (I donu2019t use egg wash) and place the pastry u201cropesu201d along the edges to from a wall sealing the edges neatly and the tips of the u201cropesu201d together.
Fill each crostatina with the apple pie filling and then use the pastry strips to make a lattice over each one, sealing it with a little milk. Brush milk ober the top of the crostatine and bake them at 190C (375F) for about 20 to 25 minutes till theyu2019re golden brown n colour.
Serve them warm as they are or with vanilla ice-cream.