In Italy the basic crostata is made with a thick layer of good jam, preferably homemade, sandwiched between the bottom crust and a lattice top. Summer is a delicious season for crostatas. One can use fresh fruit cooked down a bit with sugar to make a quick jam. Almost any fruit, fresh or frozen, from strawberries, peaches and blueberries to figs can be used for the fillings. The jam for the filling can be stored in an airtight container for up to two 2 weeks. I like to make the pastry the day before and refrigerate it overnight night. This is a very accommodating recipe. A joy to make. The perfect dessert.