Early fall—before the onset of the holiday crazies—is a great time to relax and get cozy. Apples are at their peak, and rustic, uncomplicated desserts that naturally showcase their flavor and sweetness are par for the course. It’s time for a crostata. A crostata is essentially a free-form tart. It’s easy to make, with no fuss in perfecting the shape. The filling is all about the fruit, coated in a shower of sugar and spice, then mounded in the center of the dough, which is then folded over the edges to frame and contain it. It’s simple and unadorned, and that’s the attraction. The dough can be prepared in advance and frozen if needed. Simply defrost the dough overnight in the refrigerator before rolling. When you get to the rolling stage, aim for a circle, but if the edges are uneven, you can smooth them—or leave them as they are. …